The harvesting time of fresh tea leaves has a significant impact on product yield and quality.The aim of this study was to propose a method for real-time monitoring of the optimum harvesting time for picking fresh tea...The harvesting time of fresh tea leaves has a significant impact on product yield and quality.The aim of this study was to propose a method for real-time monitoring of the optimum harvesting time for picking fresh tea leaves based on machine vision.Firstly,the shapes of fresh tea leaves were distinguished from RGB images of the tea-tree canopy after graying with the improved B-G algorithm,filtering with a median filter algorithm,binary processing with the Otsu algorithm,and noise reduction and edge smoothing using open and close operations.Then the leaf characteristics,such as leaf area index,average length,and leaf identification index,were calculated.Based on these,the Bayesian discriminant principle and method were used to construct a discriminant model for fresh tea-leaf collection status.When this method was applied to a RGB tea-tree canopy image acquired at 45°shooting angle,the fresh tea-leaf recognition rate was 90.3%,and the accuracy for fresh tea-leaf harvesting status was 98%by cross validation.Hence,this method provides the basic conditions for future tea-plantation operation and management using information technology,automation,and intelligent systems.展开更多
A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution deposite...A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution deposited by this novel technique have a It is demonstrated that the Ni-P coatings crystallized Ni-P solid solution structure, showing fine-grains, higher hardness, and higher corrosion resistance compared with the conventional electroless plated amorphous Ni-P coatings. After heat treatment at 400 ℃ for 1 h, the structure of such Ni-P coatings were transformed to a structure with Ni-Ni3P double phases, and cracks in these coatings could not be observed, whereas cracks appeared seriously in the conventional electroless plated Ni-P coating after same heat treatment. Therefore, both hardness and corrosion resistance of these Ni-P coatings can be improved further by heat treatment. All of these beneficial effects can be attributed to the role of mechanical attrition during the mechanically assisted electroless barrel-plating process.展开更多
A genetic algorithm(GA)-based new method is designed to evaluate thecircularity error of mechanical parts. The method uses the capability of nonlinear optimization ofGA to search for the optimal solution of circularit...A genetic algorithm(GA)-based new method is designed to evaluate thecircularity error of mechanical parts. The method uses the capability of nonlinear optimization ofGA to search for the optimal solution of circularity error. The finely-designed GA (FDGA)characterized dynamical bisexual recombination and Gaussian mutation. The mathematical model of thenonlinear problem is given. The implementation details in FDGA are described such as the crossoveror recombination mechanism which utilized a bisexual reproduction scheme and the elitist reservationmethod; and the adaptive mutation which used the Gaussian probability distribution to determine thevalues of the offspring produced by mutation mechanism. The examples are provided to verify thedesigned FDGA. The computation results indicate that the FDGA works very well in the field of formerror evaluation such as circularity evaluation.展开更多
Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and mo...Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and molecular levels first,and then initiate the interaction with trophectoderm.Any perturbation during this process will result in implantation failure or long-term adverse pregnancy outcomes.Endocrine steroid hormones,which function through nuclear receptors,combine with the local molecules produced by the uteri or embryo to facilitate implantation.The insulin-like growth factor(IGF)signaling has been reported to play a vital role during pregnancy.However,its physiological function during implantation remains elusive.This study revealed that mice with conditional deletion of Igflr gene in uteri suffered from subfertility,mainly due to the disturbed uterine receptivity and abnormal embryo implantation.Mechanistically,we uncovered that in response to the nidatory estrogen on D4 of pregnancy,the epithelial IGF1R,stimulated by the stromal cell-produced IGF1,facilitated epithelial STAT3 activation to modulate the epithelial depolarity.Furthermore,embryonic derived IGF2 could activate both the epithelial ERK1/2 and STAT3 signaling through IGF1R,which was critical for the transcription of Cox2 and normal attachment reaction.In brief,our data revealed that epithelial IGF1R was sequentially activated by the uterine stromal IGF1 and embryonic IGF2 to guarantee normal epithelium differentiation during the implantation process.展开更多
A mechanically assisted electroless （MAE） barrel-plating technique has been developed to deposit Ni-P coatings on carbon steel.The mechanical treatment was carried out in a rolling drum containing carbon steel speci...A mechanically assisted electroless （MAE） barrel-plating technique has been developed to deposit Ni-P coatings on carbon steel.The mechanical treatment was carried out in a rolling drum containing carbon steel specimens and glass balls of 2-3 mm diameter,which was submerged in a bath containing electroless plating solution.The coatings are Ni-polycrystalline and have a fine grained structure and smooth surfaces.The hardness and corrosion resistance of the novel coatings are considerably improved compared with the conventional electroless （CE）-plated Ni-P coatings,which are amorphous.After heat treatment at 400 C for one hour,cracks and pores are observed in the CE-plated Ni-P coating,while no cracks appear in the MAE barrel-plated Ni-P coating.The improved properties of the MAE barrel-plated Ni-P coatings demonstrate the advantages of this novel technique,wide applications of which will be found in industries.展开更多
<strong>Rationale:</strong> The three-dimensional (3D) computer-made titanium mesh is widely used in the skull repair for those patients receiving decompression of the bone flap. It can restore normal anat...<strong>Rationale:</strong> The three-dimensional (3D) computer-made titanium mesh is widely used in the skull repair for those patients receiving decompression of the bone flap. It can restore normal anatomy to a greater extent and make a better appearance. <strong>Case Presentation: </strong>We reported two cases of patients admitted to our hospital who have experienced high scalp tension after skull repair. At first, these two patients underwent decompression of the bone flap, and the physical examination results showed a defect of skull. No neurological symptoms and signs were found. The 3D computed tomography (CT) reconstruction of skull was performed, and then the skull repair with 3D titanium mesh was conducted. But because of high scalp tension, they underwent a second operation, during which we re-trimmed and reduce the arc of the titanium mesh. The scalp incision of both patients healed well and no titanium mesh was exposed. Both patients have a good prognosis. <strong>Lessons:</strong> We highlight that the high tension of scalp due to overstretching after 3D titanium mesh repair for skull defect should be paid much attention to. Trimming and reducing the arc of titanium mesh is an effective treatment for this situation.展开更多
A cathodic plasma electrolytic nitriding(CPEN)treatment with a urea aqueous solution was performed on 316L stainless steel to rapidly improve its surface properties in this work.Test results show that the PEG2000 macr...A cathodic plasma electrolytic nitriding(CPEN)treatment with a urea aqueous solution was performed on 316L stainless steel to rapidly improve its surface properties in this work.Test results show that the PEG2000 macromolecules increased the nitriding energy via enhancing the ability to bond the produced gas film to the metal/electrolyte interface.The cross-sectional morphologies indicate that a thick nitrided layer was obtained when the urea concentration was 543 g I^-1,corresponding to a Vickers hardness 450 HV(0.1),which was 3.5 times larger than that of the substrate.The nitrided layer mainly contained expanded austenite(γN),oxides and iron nitrides(e.g.,Fe3O4 and FeN(0.076)).In terms of its performance,coefficient of friction(COF)of the nitride layer decreased to nearly two-thirds that of the untreated layer,and the passivation current densities of the nitrided sample in a 3.5%NaCl solution decreased by an order of magnitude compared to that of the substrate.Therefore,the approach presented herein provides an attractive way to modify the effect of CPEN in a urea aqueous solution.展开更多
The health monitoring and fault diagnosis of heavy-duty engines are increasingly important for energy storage ecosystem. During operation, vibration characters corresponding to the specific fault need to be extracted ...The health monitoring and fault diagnosis of heavy-duty engines are increasingly important for energy storage ecosystem. During operation, vibration characters corresponding to the specific fault need to be extracted from the overall system vibration. Faulty characteristics emanating from one single cylinder are also mixed with those from other cylinders. Besides, the change of working condition brings strong nonlinearities in surface vibration. To solve these problems, an improved deep residual shrinkage network (IDRSN) is developed for detecting diverse engine faults at various degrees using single channel surface vibration signal. Within IDRSN, a wide convolution kernel is utilized in first convolution layer to capture the long-term fault-related impacts and eliminate the short-time random impact. The residual network module is adopted to enhance the focus the relevant components of vibration signals. Mini-batch training strategy is used to improve the model stability. Meanwhile, Gradient-weighted class activation map is adopted to assess the consistency between the learned knowledge and the fault-related information. The IDRSN is implemented to diagnosing a diesel engine under various faults, faulty degrees and operating speeds. Comparisons with existing models are analyzed in terms of hyper-parameters, training samples, noise resistance, and visualization. Results demonstrate the proposed IDRSN's superior performance on fault diagnosis accuracy, stability, anti-noise performance, and anti-interference performance. An average accuracy rate of 98.38 % was achieved by the proposed IDRSN, in comparison to 96.64 % and 93.56 % achieved by the DRSN and the wide-kernel deep convolutional neural network respectively. These results highlight the proposed IDRSN's superiority in diagnosing multiple faults under various working conditions, offering a low-cost, highly effective, and applicable approach for complex fault diagnosis tasks.展开更多
<strong>Objective:</strong> To retrospectively analyze the clinical utility of quantitative nursing measures of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery to provid...<strong>Objective:</strong> To retrospectively analyze the clinical utility of quantitative nursing measures of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery to provide the experience for improving the recovery rate and living quality of these patients. <strong>Methods:</strong> The clinical data of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery was analyzed. For problems such as dysphagia and dyspnea of these patients, the nursing care focused on strict monitoring, timely oxygen inhalation nursing, posture nursing, ventilator nursing, swallowing function training, etc. <strong>Results:</strong> After received quantitative care, 10 patients with lower cranial nerves injury after cerebellopontine angle tumors surgery were recovered well, and their symptoms such as dysphagia and dyspnea were gradually improved and safely discharged. <strong>Conclusion:</strong> Lower cranial nerves injury is one of the serious complications after removal of cerebellopontine angle tumors, which impacts the life and health of patients. Caregivers should accurately understand and analyze the symptoms, and quantitative and targeted nursing measures for posterior cranial nerves injury are helpful in the postoperative rehabilitation of patients and improve their living quality.展开更多
The solid template CCD camera calibration method of bundle adjustments basedon collinearity equation is presented considering the characteristics of space large-dimensionon-line measurement. In the method, a more comp...The solid template CCD camera calibration method of bundle adjustments basedon collinearity equation is presented considering the characteristics of space large-dimensionon-line measurement. In the method, a more comprehensive camera model is adopted which is based onthe pinhole model extended with distortions corrections. In the process of calibration, calibrationprecision is improved by imaging at different locations in the whole measurement space,multi-imaging at the same location and bundle adjustments optimization. The calibration experimentproves that the calibration method is able to fulfill calibration requirement of CCD camera appliedto vision measurement.展开更多
The surface properties of the air-plasma sprayed bond-coat have been modified by cathode plasma electrolysis（CPE）. After modification, a re-melted layer without obvious pores and oxide stringers is formed,the gain s...The surface properties of the air-plasma sprayed bond-coat have been modified by cathode plasma electrolysis（CPE）. After modification, a re-melted layer without obvious pores and oxide stringers is formed,the gain size of re-melted layer is approximately 80–120 nm. It is shown, from cyclic oxidation at 1100℃,that a thin oxide scale mainly composed of α-Al;O;has been formed on the modified bond-coat and the oxidation resistance of the modified bond-coat has been significantly improved. Such beneficial result can be attributed to following effects: during CPE process, the plasma discharges with high temperature take place on the bond-coat surface. With plasma discharge treatment, the surface is melted and quickly re-solidified, the grain size decreases, and the pores and oxide stringers disappear. During cyclic oxidation, owing to the above modification of surface properties, the critical content of Al for selective oxidation is significantly decreased. Therefore, a continuous Al;O;scale is formed.展开更多
Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition （MA）. The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizon...Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition （MA）. The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizontal direction. The experimental results show that, under the assistant of MA action, the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively, and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles, and the hardness and corrosion resistance of these coatings increase markedly. During heat treatment, the defects produced in conventional Ni-P-SiC composite coatings can be avoided assisted by MA action. Both of the wear of these coatings can be improved further.展开更多
Micro-crystalline coatings of 310S stainless steels were produced by unbalanced magnetron sputter deposition. Isothermal oxidation behavior of the coated and uncoated specimens has been studied using a thermogravimetr...Micro-crystalline coatings of 310S stainless steels were produced by unbalanced magnetron sputter deposition. Isothermal oxidation behavior of the coated and uncoated specimens has been studied using a thermogravimetric analysis (TGA) station. The oxidation time was 50h and the temperature was 1 000℃. The oxidation rates of thecoated specimens was found to be much lower than the uncoated specimens after 50 h of oxidation. The oxidationkinetic curves of the coated specimens consisted of three stages : approximately parabolic at the first stage, speedingup at the second stage, and slow down at the third stage. The increase of the oxidation rate at the second stage nasattributed to the fast diffuison of Fe though the fine grained Cr2O3 layer formed on the micro-crystalline coatings.The top view and cross-section microstructures of the oxides formed on the coated and the uncoated specimens werestudied with SEM and EDS. It was observed that the nucleation of oxide on the coated specimens was muchenhanced at the initial oxidation stage. This was explained as the result of reduction in the critical free energychange and increase in the supply of chromium ions.展开更多
Growth and passivation of tunnels within Al foil by on-off controlling DC etching in 6 wt.% HCI solution has been investigated. It was found that, in a given etchant solution at a special temperature, the longest tunn...Growth and passivation of tunnels within Al foil by on-off controlling DC etching in 6 wt.% HCI solution has been investigated. It was found that, in a given etchant solution at a special temperature, the longest tunnel length was only a function of the turn-on interval of DC. The potential of Al foil broke at on-off controlling DC by the result from anode polarization curves and potential-time （E-t） responding curves. When DC was switched on, the potential increased abruptly over pitting potential, leading to nucleation of pits at the surface and the growth of tunnels at special length. When DC was switched off, the potential decreased rapidly to a passive value, leading to stoppage of nucleation and death of tunnels. By this way, the longest tunnel length can be controlled and a non-piercing layer can be obtained. Hence, etching of Al foil at this current is beneficial for maintaining a good mechanical strength.展开更多
This paper studies the properties of solutions of quasilinear equations involving the p-laplacian type operator in general Carnot-Caratheodory spaces. The authors show some comparison results for solutions of the rele...This paper studies the properties of solutions of quasilinear equations involving the p-laplacian type operator in general Carnot-Caratheodory spaces. The authors show some comparison results for solutions of the relevant differential inequalities and use them to get some symmetry and monotonicity properties of solutions, in bounded or unbounded domains.展开更多
Nitrogen(N)deposition has a profound influence on forest soil carbon(C)and N pools,but there was no consensus on the responses of different C and N components in different forest types.In this study,a two-year simulat...Nitrogen(N)deposition has a profound influence on forest soil carbon(C)and N pools,but there was no consensus on the responses of different C and N components in different forest types.In this study,a two-year simulated N deposition experiment with four levels of N(NH4NO3)-addition treatments(0,50,100,and 150 kg N/hm^(2)·a)were conducted in Larix gmelinii(LG)and Quercus mongolica(QM)plantation in Northeast China,in order to investigate the C and N pool dynamics under continuously enhanced N deposition.Soil organic carbon(SOC),soil total N(STN)and their active components(readily oxidizable C,ROC;dissolved organic C,DOC;microbial biomass C,MBC,dissolved organic N,DON;microbial biomass N,MBN)of the forest soil were measured monthly from May to October 2017.C and N contents in LG were observed higher than in QM.N addition had no effect on SOC and STN of LG,but significantly increased SOC and STN of QM at low N addition level.Low N addition generally raised active C components(ROC,DOC,and MBC)in both plantations,whereas high N addition did not significantly affect these components,or even decreased ROC in LG soil.Low N addition also increased STN and MBN of QM,while no significant change in STN and MBN of LG was observed.DON was directly affected by N addition and increased significantly with elevated N addition levels.The results indicated that N addition,especially of low rate,might enhance the C sequestration capacity of the forest soils and mitigate climate change.展开更多
Tritium permeation barriers on stainless steels are required in fusion technology in order to reduce the tritium permeation rate through the structural material into the cooling water system.Preparation of tritium per...Tritium permeation barriers on stainless steels are required in fusion technology in order to reduce the tritium permeation rate through the structural material into the cooling water system.Preparation of tritium permeation barrier Al2O3 is an important way to solve the problem of leakage of tritium permeation.It is worth to note that the noble Au is an excellent barrier of hydrogen dissolution.Al2O3/Au composite coating was designed for potential tritium permeation barrier on stainless steel.The alternation coatings have been prepared by electrochemical deposition method.The processing parameters and subsequent sinter temperature for composite coatings were optimized.The oxidation resistance of the coating has been tested.A hydrogen diffusion test simulating tritium permeation has been conducted to compare the sample with and without coating.Microstructure was examined by scanning electron microcopy(SEM).The results showed Al2O3/Au multi-alternation coatings can be prepared on the surface of stainless steel at the case of controlling processing well.The coatings have the characteristic of high temperature oxidation resistance and good hydrogen permeability barrier.The tritium permeation should be study further.展开更多
Objective:The study aims to explore the interventional effect of Abrus cantonensis and Armeniaca mume Sieb and their compatibility on blood glucose and blood lipid in diabetic mice and to explore the optimal ratio of ...Objective:The study aims to explore the interventional effect of Abrus cantonensis and Armeniaca mume Sieb and their compatibility on blood glucose and blood lipid in diabetic mice and to explore the optimal ratio of efficacy of their compatibility.Methods:SPF Kunming male mice were fed with high sugar and high fat diet for 6 weeks and then intraperitoneally injected with STZ solution to establish a diabetes model.The successfully modeled mice were randomly divided into 6 groups according to their body weight:model group,Abrus Cantoniensis group,Armeniaca mume Sieb group,as well as Abrus Cantoniensis and Armeniaca mume Sieb group divided into 1:2,1:1 and 2:1 groups according to volume ratio with 10 mice in each group.Another 10 healthy mice were taken as blank group and intraperitoneally injected with sodium citrate buffer.The corresponding solution was given intragastric administration by body mass once a day for 20 days.After the last administration,fasting was performed for 12 hours.Serum was collected by the method of eyeball blood collection to determine the contents of fasting blood glucose,total cholesterol Triacylglycerol,triglyceride,low density lipoprotein and high-density lipoprotein.Results:Compared with Abrus Cantoniensis and Armeniaca mume Sieb groups,Glu,TG,TC and LDL-C of the three compatibility groups significantly decreased,with the most significant decrease in the compatibility group 1:2,while there was no significant difference in HDL-C among all groups.Conclusion:Abrus Cantoniensis and Armeniaca mume Sieb and their combination have synergistic effects on the improvement of blood glucose and lipid levels in mice with high glucose and high fat combined with STZ-induced diabetes mellitus model.Among all the experimental groups,the compatibility 1:2 group had the best effect.展开更多
In this paper, we review the evolution of 12CrlMoV steel standards at home and abroad, analyze the effects of various elements and determine their optimal contents in steel. The influence of heat treatment and microst...In this paper, we review the evolution of 12CrlMoV steel standards at home and abroad, analyze the effects of various elements and determine their optimal contents in steel. The influence of heat treatment and microstructure on the creep strength of 12CrlMoV steel is investigated. Statistical results from conventional mechanical properties, ductile-brittle transition temperature, high temperature oxidation resistance, aging, instant high temperature properties, and creep are introduced. The results show that the chemical composition and heat treatment process of 12CrlMoVG steel identified in the GB 5310 - 2008 standard is appropriate, resulting in a steel with higher creep strength and good comprehensive properties.展开更多
基金This work was financially supported in part by Programs(2018YFD0200803),(2017RS3061),(2018GK2013),(2017NK2382),(2017YFD0301507)and(2018JJ3227).
文摘The harvesting time of fresh tea leaves has a significant impact on product yield and quality.The aim of this study was to propose a method for real-time monitoring of the optimum harvesting time for picking fresh tea leaves based on machine vision.Firstly,the shapes of fresh tea leaves were distinguished from RGB images of the tea-tree canopy after graying with the improved B-G algorithm,filtering with a median filter algorithm,binary processing with the Otsu algorithm,and noise reduction and edge smoothing using open and close operations.Then the leaf characteristics,such as leaf area index,average length,and leaf identification index,were calculated.Based on these,the Bayesian discriminant principle and method were used to construct a discriminant model for fresh tea-leaf collection status.When this method was applied to a RGB tea-tree canopy image acquired at 45°shooting angle,the fresh tea-leaf recognition rate was 90.3%,and the accuracy for fresh tea-leaf harvesting status was 98%by cross validation.Hence,this method provides the basic conditions for future tea-plantation operation and management using information technology,automation,and intelligent systems.
基金supported by the National Natural Science Foundation of China (Grant No.50671006)the National R&D Infrastructure and Facility Development Program of China (2005DKA10400-Z1)
文摘A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution deposited by this novel technique have a It is demonstrated that the Ni-P coatings crystallized Ni-P solid solution structure, showing fine-grains, higher hardness, and higher corrosion resistance compared with the conventional electroless plated amorphous Ni-P coatings. After heat treatment at 400 ℃ for 1 h, the structure of such Ni-P coatings were transformed to a structure with Ni-Ni3P double phases, and cracks in these coatings could not be observed, whereas cracks appeared seriously in the conventional electroless plated Ni-P coating after same heat treatment. Therefore, both hardness and corrosion resistance of these Ni-P coatings can be improved further by heat treatment. All of these beneficial effects can be attributed to the role of mechanical attrition during the mechanically assisted electroless barrel-plating process.
基金The project is supported by National Natural Science Foundation of China(No.59975025).
文摘A genetic algorithm(GA)-based new method is designed to evaluate thecircularity error of mechanical parts. The method uses the capability of nonlinear optimization ofGA to search for the optimal solution of circularity error. The finely-designed GA (FDGA)characterized dynamical bisexual recombination and Gaussian mutation. The mathematical model of thenonlinear problem is given. The implementation details in FDGA are described such as the crossoveror recombination mechanism which utilized a bisexual reproduction scheme and the elitist reservationmethod; and the adaptive mutation which used the Gaussian probability distribution to determine thevalues of the offspring produced by mutation mechanism. The examples are provided to verify thedesigned FDGA. The computation results indicate that the FDGA works very well in the field of formerror evaluation such as circularity evaluation.
基金supported by the National Key R&D Program of China(2017YFC1001402 to H.W.2018YFC1004401 to S.K.)+1 种基金the National Natural Science Foundation of China(81830045 and 82030040 to H.W.,81971388 to S.K.)Institution of Higher Education Projects of Building First-class Discipline Construction in Ningxia Region(NXYLXK2017B05 to G.X.).
文摘Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and molecular levels first,and then initiate the interaction with trophectoderm.Any perturbation during this process will result in implantation failure or long-term adverse pregnancy outcomes.Endocrine steroid hormones,which function through nuclear receptors,combine with the local molecules produced by the uteri or embryo to facilitate implantation.The insulin-like growth factor(IGF)signaling has been reported to play a vital role during pregnancy.However,its physiological function during implantation remains elusive.This study revealed that mice with conditional deletion of Igflr gene in uteri suffered from subfertility,mainly due to the disturbed uterine receptivity and abnormal embryo implantation.Mechanistically,we uncovered that in response to the nidatory estrogen on D4 of pregnancy,the epithelial IGF1R,stimulated by the stromal cell-produced IGF1,facilitated epithelial STAT3 activation to modulate the epithelial depolarity.Furthermore,embryonic derived IGF2 could activate both the epithelial ERK1/2 and STAT3 signaling through IGF1R,which was critical for the transcription of Cox2 and normal attachment reaction.In brief,our data revealed that epithelial IGF1R was sequentially activated by the uterine stromal IGF1 and embryonic IGF2 to guarantee normal epithelium differentiation during the implantation process.
基金supported by the NationalNatural Science Foundation of China(No.50671006)
文摘A mechanically assisted electroless （MAE） barrel-plating technique has been developed to deposit Ni-P coatings on carbon steel.The mechanical treatment was carried out in a rolling drum containing carbon steel specimens and glass balls of 2-3 mm diameter,which was submerged in a bath containing electroless plating solution.The coatings are Ni-polycrystalline and have a fine grained structure and smooth surfaces.The hardness and corrosion resistance of the novel coatings are considerably improved compared with the conventional electroless （CE）-plated Ni-P coatings,which are amorphous.After heat treatment at 400 C for one hour,cracks and pores are observed in the CE-plated Ni-P coating,while no cracks appear in the MAE barrel-plated Ni-P coating.The improved properties of the MAE barrel-plated Ni-P coatings demonstrate the advantages of this novel technique,wide applications of which will be found in industries.
文摘<strong>Rationale:</strong> The three-dimensional (3D) computer-made titanium mesh is widely used in the skull repair for those patients receiving decompression of the bone flap. It can restore normal anatomy to a greater extent and make a better appearance. <strong>Case Presentation: </strong>We reported two cases of patients admitted to our hospital who have experienced high scalp tension after skull repair. At first, these two patients underwent decompression of the bone flap, and the physical examination results showed a defect of skull. No neurological symptoms and signs were found. The 3D computed tomography (CT) reconstruction of skull was performed, and then the skull repair with 3D titanium mesh was conducted. But because of high scalp tension, they underwent a second operation, during which we re-trimmed and reduce the arc of the titanium mesh. The scalp incision of both patients healed well and no titanium mesh was exposed. Both patients have a good prognosis. <strong>Lessons:</strong> We highlight that the high tension of scalp due to overstretching after 3D titanium mesh repair for skull defect should be paid much attention to. Trimming and reducing the arc of titanium mesh is an effective treatment for this situation.
基金supported financially by the National Natural Science Foundation of China (No.51771027)the Fundamental Research Funds for the Central Universities (No.FRF-BD-18-019A)+1 种基金the National Key Research and Development Program of China (No. 2017YFB0702100)the National Environmental Corrosion Platform
文摘A cathodic plasma electrolytic nitriding(CPEN)treatment with a urea aqueous solution was performed on 316L stainless steel to rapidly improve its surface properties in this work.Test results show that the PEG2000 macromolecules increased the nitriding energy via enhancing the ability to bond the produced gas film to the metal/electrolyte interface.The cross-sectional morphologies indicate that a thick nitrided layer was obtained when the urea concentration was 543 g I^-1,corresponding to a Vickers hardness 450 HV(0.1),which was 3.5 times larger than that of the substrate.The nitrided layer mainly contained expanded austenite(γN),oxides and iron nitrides(e.g.,Fe3O4 and FeN(0.076)).In terms of its performance,coefficient of friction(COF)of the nitride layer decreased to nearly two-thirds that of the untreated layer,and the passivation current densities of the nitrided sample in a 3.5%NaCl solution decreased by an order of magnitude compared to that of the substrate.Therefore,the approach presented herein provides an attractive way to modify the effect of CPEN in a urea aqueous solution.
基金funded by the National Key R&D Program of China(Grant No.2021YFD2000303)Tianjin Research Innovation Project for Postgraduate Students in China(Grant No.2021YJSB182)Weichai Power Co.,Ltd.in China(Grant No.WCDL-GH-2023-0147).
文摘The health monitoring and fault diagnosis of heavy-duty engines are increasingly important for energy storage ecosystem. During operation, vibration characters corresponding to the specific fault need to be extracted from the overall system vibration. Faulty characteristics emanating from one single cylinder are also mixed with those from other cylinders. Besides, the change of working condition brings strong nonlinearities in surface vibration. To solve these problems, an improved deep residual shrinkage network (IDRSN) is developed for detecting diverse engine faults at various degrees using single channel surface vibration signal. Within IDRSN, a wide convolution kernel is utilized in first convolution layer to capture the long-term fault-related impacts and eliminate the short-time random impact. The residual network module is adopted to enhance the focus the relevant components of vibration signals. Mini-batch training strategy is used to improve the model stability. Meanwhile, Gradient-weighted class activation map is adopted to assess the consistency between the learned knowledge and the fault-related information. The IDRSN is implemented to diagnosing a diesel engine under various faults, faulty degrees and operating speeds. Comparisons with existing models are analyzed in terms of hyper-parameters, training samples, noise resistance, and visualization. Results demonstrate the proposed IDRSN's superior performance on fault diagnosis accuracy, stability, anti-noise performance, and anti-interference performance. An average accuracy rate of 98.38 % was achieved by the proposed IDRSN, in comparison to 96.64 % and 93.56 % achieved by the DRSN and the wide-kernel deep convolutional neural network respectively. These results highlight the proposed IDRSN's superiority in diagnosing multiple faults under various working conditions, offering a low-cost, highly effective, and applicable approach for complex fault diagnosis tasks.
文摘<strong>Objective:</strong> To retrospectively analyze the clinical utility of quantitative nursing measures of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery to provide the experience for improving the recovery rate and living quality of these patients. <strong>Methods:</strong> The clinical data of 10 cases of lower cranial nerves injury after cerebellopontine angle tumors surgery was analyzed. For problems such as dysphagia and dyspnea of these patients, the nursing care focused on strict monitoring, timely oxygen inhalation nursing, posture nursing, ventilator nursing, swallowing function training, etc. <strong>Results:</strong> After received quantitative care, 10 patients with lower cranial nerves injury after cerebellopontine angle tumors surgery were recovered well, and their symptoms such as dysphagia and dyspnea were gradually improved and safely discharged. <strong>Conclusion:</strong> Lower cranial nerves injury is one of the serious complications after removal of cerebellopontine angle tumors, which impacts the life and health of patients. Caregivers should accurately understand and analyze the symptoms, and quantitative and targeted nursing measures for posterior cranial nerves injury are helpful in the postoperative rehabilitation of patients and improve their living quality.
文摘The solid template CCD camera calibration method of bundle adjustments basedon collinearity equation is presented considering the characteristics of space large-dimensionon-line measurement. In the method, a more comprehensive camera model is adopted which is based onthe pinhole model extended with distortions corrections. In the process of calibration, calibrationprecision is improved by imaging at different locations in the whole measurement space,multi-imaging at the same location and bundle adjustments optimization. The calibration experimentproves that the calibration method is able to fulfill calibration requirement of CCD camera appliedto vision measurement.
基金financially supported by the National Natural Science Foundation of China (Grant No. 51271030)
文摘The surface properties of the air-plasma sprayed bond-coat have been modified by cathode plasma electrolysis（CPE）. After modification, a re-melted layer without obvious pores and oxide stringers is formed,the gain size of re-melted layer is approximately 80–120 nm. It is shown, from cyclic oxidation at 1100℃,that a thin oxide scale mainly composed of α-Al;O;has been formed on the modified bond-coat and the oxidation resistance of the modified bond-coat has been significantly improved. Such beneficial result can be attributed to following effects: during CPE process, the plasma discharges with high temperature take place on the bond-coat surface. With plasma discharge treatment, the surface is melted and quickly re-solidified, the grain size decreases, and the pores and oxide stringers disappear. During cyclic oxidation, owing to the above modification of surface properties, the critical content of Al for selective oxidation is significantly decreased. Therefore, a continuous Al;O;scale is formed.
基金supported by the National Natural Science Foundation of China (No.50671006)
文摘Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition （MA）. The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizontal direction. The experimental results show that, under the assistant of MA action, the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively, and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles, and the hardness and corrosion resistance of these coatings increase markedly. During heat treatment, the defects produced in conventional Ni-P-SiC composite coatings can be avoided assisted by MA action. Both of the wear of these coatings can be improved further.
文摘Micro-crystalline coatings of 310S stainless steels were produced by unbalanced magnetron sputter deposition. Isothermal oxidation behavior of the coated and uncoated specimens has been studied using a thermogravimetric analysis (TGA) station. The oxidation time was 50h and the temperature was 1 000℃. The oxidation rates of thecoated specimens was found to be much lower than the uncoated specimens after 50 h of oxidation. The oxidationkinetic curves of the coated specimens consisted of three stages : approximately parabolic at the first stage, speedingup at the second stage, and slow down at the third stage. The increase of the oxidation rate at the second stage nasattributed to the fast diffuison of Fe though the fine grained Cr2O3 layer formed on the micro-crystalline coatings.The top view and cross-section microstructures of the oxides formed on the coated and the uncoated specimens werestudied with SEM and EDS. It was observed that the nucleation of oxide on the coated specimens was muchenhanced at the initial oxidation stage. This was explained as the result of reduction in the critical free energychange and increase in the supply of chromium ions.
基金This study was financially supported by Beijing Education Commission,China.
文摘Growth and passivation of tunnels within Al foil by on-off controlling DC etching in 6 wt.% HCI solution has been investigated. It was found that, in a given etchant solution at a special temperature, the longest tunnel length was only a function of the turn-on interval of DC. The potential of Al foil broke at on-off controlling DC by the result from anode polarization curves and potential-time （E-t） responding curves. When DC was switched on, the potential increased abruptly over pitting potential, leading to nucleation of pits at the surface and the growth of tunnels at special length. When DC was switched off, the potential decreased rapidly to a passive value, leading to stoppage of nucleation and death of tunnels. By this way, the longest tunnel length can be controlled and a non-piercing layer can be obtained. Hence, etching of Al foil at this current is beneficial for maintaining a good mechanical strength.
基金National Natural Science Foundation of China(No.10071023)MOST and Foundation for University Key TeacherShanghai Priority Academic Discipline
文摘This paper studies the properties of solutions of quasilinear equations involving the p-laplacian type operator in general Carnot-Caratheodory spaces. The authors show some comparison results for solutions of the relevant differential inequalities and use them to get some symmetry and monotonicity properties of solutions, in bounded or unbounded domains.
基金This work was supported by the National Key Research and Development Program of China(grant No.2016YFD0200304,2017YFC0504205).
文摘Nitrogen(N)deposition has a profound influence on forest soil carbon(C)and N pools,but there was no consensus on the responses of different C and N components in different forest types.In this study,a two-year simulated N deposition experiment with four levels of N(NH4NO3)-addition treatments(0,50,100,and 150 kg N/hm^(2)·a)were conducted in Larix gmelinii(LG)and Quercus mongolica(QM)plantation in Northeast China,in order to investigate the C and N pool dynamics under continuously enhanced N deposition.Soil organic carbon(SOC),soil total N(STN)and their active components(readily oxidizable C,ROC;dissolved organic C,DOC;microbial biomass C,MBC,dissolved organic N,DON;microbial biomass N,MBN)of the forest soil were measured monthly from May to October 2017.C and N contents in LG were observed higher than in QM.N addition had no effect on SOC and STN of LG,but significantly increased SOC and STN of QM at low N addition level.Low N addition generally raised active C components(ROC,DOC,and MBC)in both plantations,whereas high N addition did not significantly affect these components,or even decreased ROC in LG soil.Low N addition also increased STN and MBN of QM,while no significant change in STN and MBN of LG was observed.DON was directly affected by N addition and increased significantly with elevated N addition levels.The results indicated that N addition,especially of low rate,might enhance the C sequestration capacity of the forest soils and mitigate climate change.
文摘Tritium permeation barriers on stainless steels are required in fusion technology in order to reduce the tritium permeation rate through the structural material into the cooling water system.Preparation of tritium permeation barrier Al2O3 is an important way to solve the problem of leakage of tritium permeation.It is worth to note that the noble Au is an excellent barrier of hydrogen dissolution.Al2O3/Au composite coating was designed for potential tritium permeation barrier on stainless steel.The alternation coatings have been prepared by electrochemical deposition method.The processing parameters and subsequent sinter temperature for composite coatings were optimized.The oxidation resistance of the coating has been tested.A hydrogen diffusion test simulating tritium permeation has been conducted to compare the sample with and without coating.Microstructure was examined by scanning electron microcopy(SEM).The results showed Al2O3/Au multi-alternation coatings can be prepared on the surface of stainless steel at the case of controlling processing well.The coatings have the characteristic of high temperature oxidation resistance and good hydrogen permeability barrier.The tritium permeation should be study further.
基金This work was supported by National Natural Science Foundation of China(No.81360684)Guangxi Key Research and Development Plan Project(Gui Ke AB18221095)+3 种基金Teaching Teacher Training Project from Youjiang Medical University for Nationalities-National Teaching Teacher Training Project(You Hospital Zi[2018]No.98)High-level Talent Research Projects from Youjiang Medical University For Nationalities(No.01002018079)China National and Regional University Students Innovation and Entrepreneurship Training Scheme Funding(No.202010599022)China Regional University Students Innovation and Entrepreneurship Training Scheme Funding(No.202010599073).
文摘Objective:The study aims to explore the interventional effect of Abrus cantonensis and Armeniaca mume Sieb and their compatibility on blood glucose and blood lipid in diabetic mice and to explore the optimal ratio of efficacy of their compatibility.Methods:SPF Kunming male mice were fed with high sugar and high fat diet for 6 weeks and then intraperitoneally injected with STZ solution to establish a diabetes model.The successfully modeled mice were randomly divided into 6 groups according to their body weight:model group,Abrus Cantoniensis group,Armeniaca mume Sieb group,as well as Abrus Cantoniensis and Armeniaca mume Sieb group divided into 1:2,1:1 and 2:1 groups according to volume ratio with 10 mice in each group.Another 10 healthy mice were taken as blank group and intraperitoneally injected with sodium citrate buffer.The corresponding solution was given intragastric administration by body mass once a day for 20 days.After the last administration,fasting was performed for 12 hours.Serum was collected by the method of eyeball blood collection to determine the contents of fasting blood glucose,total cholesterol Triacylglycerol,triglyceride,low density lipoprotein and high-density lipoprotein.Results:Compared with Abrus Cantoniensis and Armeniaca mume Sieb groups,Glu,TG,TC and LDL-C of the three compatibility groups significantly decreased,with the most significant decrease in the compatibility group 1:2,while there was no significant difference in HDL-C among all groups.Conclusion:Abrus Cantoniensis and Armeniaca mume Sieb and their combination have synergistic effects on the improvement of blood glucose and lipid levels in mice with high glucose and high fat combined with STZ-induced diabetes mellitus model.Among all the experimental groups,the compatibility 1:2 group had the best effect.
文摘In this paper, we review the evolution of 12CrlMoV steel standards at home and abroad, analyze the effects of various elements and determine their optimal contents in steel. The influence of heat treatment and microstructure on the creep strength of 12CrlMoV steel is investigated. Statistical results from conventional mechanical properties, ductile-brittle transition temperature, high temperature oxidation resistance, aging, instant high temperature properties, and creep are introduced. The results show that the chemical composition and heat treatment process of 12CrlMoVG steel identified in the GB 5310 - 2008 standard is appropriate, resulting in a steel with higher creep strength and good comprehensive properties.
