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Selective catalytic hydrogenation of naphthalene to tetralin over a NiMo/Al2O3 catalyst 被引量:8
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作者 Xiaoping Su Pu An +7 位作者 Junwen Gao RuchengWang Yujuan Zhang Xi Li yangkun Zhao Yongqi Liu Xiaoxun Ma Ming Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第10期2566-2576,共11页
The selective catalytic hydrogenation of naphthalene to high-value tetralin was systematically investigated.A series of Al2O3 catalysts containing different active metals(Co,Mo,Ni,W)were prepared by incipient wetness ... The selective catalytic hydrogenation of naphthalene to high-value tetralin was systematically investigated.A series of Al2O3 catalysts containing different active metals(Co,Mo,Ni,W)were prepared by incipient wetness impregnation.The effects of different active metals forms(oxidation,reduction,sulfuration)and reaction conditions on naphthalene hydrogenation were investigated and the catalysts were characterized by XRD,XPS,BET,NH3-TPD and SEM.Especially,Ni-Mo/Al2O3 was first used in this reactive system.The results show that the oxidative4%Ni O-20%MoO3/Al2O3 is the best catalyst for the preparation of tetralin.The conversion of naphthalene and the selectivity of tetralin can reach 95.62%and 99.75%respectively at 200℃,8 h and 6 MPa.Compared with reduced and sulfureted 4%Ni O-20%MoO3/Al2O3 catalysts,oxidative 4%Ni O-20%MoO3/Al2O3 has a well dispersed and uniform monolayer of the active metals,larger pore volume and size,and larger total acidity.NiO-MoO3/Al2O3 has a synergistic effect between NiO activity and MoO3 selectivity. 展开更多
关键词 NAPHTHALENE TETRALIN Ni-Mo/Al2O3 catalysts
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Thrombolysis with alteplase 3-4.5 hours after acute ischaemic stroke:the first multicentre,phase III trial in China 被引量:7
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作者 Huaguang Zheng Yi Yang +12 位作者 Huisheng Chen Chuanling Li yangkun Chen Fu-Dong Shi Li Yang Xiaoping Cui Zuneng Lu Yanling Liang Songbiao Cui Anding Xu Yiqing Wu Yaqing Sun Yongjun Wang 《Stroke & Vascular Neurology》 SCIE 2020年第3期285-290,共6页
background and purpose Data on the efficacy and safety of alteplase for acute ischaemic stroke(AIS)administered 3-4.5 hours after the onset of stroke symptoms in Chinese patients is limited.We sought to determine whet... background and purpose Data on the efficacy and safety of alteplase for acute ischaemic stroke(AIS)administered 3-4.5 hours after the onset of stroke symptoms in Chinese patients is limited.We sought to determine whether AIS patients would benefit from thrombolysis with alteplase between 3 and 4.5 hours after the onset of stroke symptoms in a prospective,multicentre,single-arm trial in China.Materials and methods Eligible AIS patients were given 0.9 mg/kg alteplase intravenously.The primary efficacy endpoint was a favourable outcome at 3 months,defined as a score of 0 or 1 on the modified Rankin Scale.Thresholds for the primary efficacy endpoint were determined to be 40%based on the literature review.The primary safety endpoint was symptomatic intracranial haemorrhage(sICH)according to the European Cooperative Acute Stroke Study III(ECASS III)trial definition.Post hoc analysis between this study and the ECASS III trial were compared using the propensity score matching(PSM)method.results A total of 120 eligible AIS patients from 11 sites in China received thrombolysis therapy in this study.The median time from onset of symptoms to needle was 3 hours 54 min.The percentage of patients with a favourable outcome was 63.3%(95%CI 54.4 to 71.4),significantly higher than the predefined threshold(p<0.0001).Three patients(2.5%,95%CI 0.5 to 7.1)had sICH,including two fatal sICH.Six patients died within 3 months after treatment.The post hoc PSM analysis showed a numerically higher rate of the primary efficacy endpoint in this study(63.3%)than the matched placebo arm(56.7%)in the ECASS III trial.Conclusions Intravenous alteplase with a standard dose administered between 3 and 4.5 hours after onset of symptoms is effective and safe for Chinese AIS patients. 展开更多
关键词 NEEDLE ACUTE CENTRE
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Photocrosslinking silver nanoparticles–aloe vera–silk fibroin composite hydrogel for treatment of full-thickness cutaneous wounds 被引量:7
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作者 yangkun Liu JinChuan Fan +9 位作者 MingQi Lv Kepeng She Jiale Sun Qingqing Lu Changhao Han SongTao Ding Shuang Zhao GuiXue Wang YuChan Zhang GuangChao Zang 《Regenerative Biomaterials》 SCIE EI 2021年第6期46-58,共13页
Damage to the skin causes physiological and functional issues.The most effective treatment approach is the use of wound dressings.Silk fibroin(SF)is a promising candidate biomaterial for regulating wound healing;howev... Damage to the skin causes physiological and functional issues.The most effective treatment approach is the use of wound dressings.Silk fibroin(SF)is a promising candidate biomaterial for regulating wound healing;however,its antibacterial properties and biological activity must be further improved.In this study,a photocrosslinking hydrogel was developed to treat full-thickness cutaneous wounds.The composite hydrogel(Ag-AV-SF hydrogel)was prepared by introducing the silver nanoparticles(AgNPs)and aloe vera(AV)as the modifiers.In vitro study exhibited great antibacterial ability,biocompatibility and cell-proliferation and-migration-promoting capacities.It also showed the pH-response releasing properties which release more AgNPs in a simulated chronic infection environment.The healing effect evaluation in vivo showed the healing-promoting ability of the Ag-AV-SF hydrogel was stronger than the single-modifiers groups,and the healing rate of it reached 97.02%on Day 21,higher than the commercial wound dressing,silver sulfadiazine(SS)cream on sale.Additionally,the histological and protein expression results showed that the Ag-AV-SF hydrogel has a greater effect on the pro-healing regenerative phenotype with M2 macrophages at the early stage,reconstructing the blood vessels networks and inhibiting the formation of scars.In summary,the Ag-AV-SF hydrogel developed in this study had good physical properties,overwhelming antibacterial properties,satisfactory biocompatibility and significantly promoting effect on cell proliferation,migration and wound healing.Overall,our results suggest that the Ag-AV-SF hydrogel we developed has great potential for improving the wound healing in clinical treatment. 展开更多
关键词 silk fibroin silver nanoparticles aloe vera HYDROGEL wound healing
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Analytical solutions for equivalent elastic compliance of cubic lattice structures subjected to hypergravity conditions
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作者 Lei Wang yangkun Du +1 位作者 Guannan Wang Chaofeng Lü 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2024年第6期11-19,共9页
In order to comprehensively understand the mechanical behavior of biological entities and aerospace applications subjected to hypergravity environments,we delve into the impact of hypergravity on the equivalent compli... In order to comprehensively understand the mechanical behavior of biological entities and aerospace applications subjected to hypergravity environments,we delve into the impact of hypergravity on the equivalent compliance of cubic lattice structures.Capitalizing on the periodic spatial distribution,we employ a unit cell methodology to deduce the homogenized stress-strain relationship for the lattice structures,subsequently obtaining the associated equivalent compliance.The equivalent compliance can be conveniently reduced to instances without hypergravity influence.Furthermore,numerical simulations are executed to validate the derivations and to illustrate that hypergravity indeed affects the mechanical properties of lattice structures.We introduce a non-dimensional hypergravity factor,which quantifies the impact of hypergravity magnitude relative to the Young’s modulus of the base material.Our findings reveal that the hypergravity factor influences perpendicular compliance quadratically and parallel compliance linearly.Simultaneously,the perpendicular shear compliance remains unaffected,whereas the parallel shear compliance experiences an inverse effect.Additionally,the lattice structure transforms into a gradient material oriented in the hypergravity direction,consequently generating a scale effect. 展开更多
关键词 HYPERGRAVITY Cubic lattice structures Equivalent compliance Unit cell approach
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Sprayed PAA-CaO_(2)nanoparticles combined with calcium ions and reactive oxygen species for antibacterial and wound healing
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作者 Hong Yu Jiale Sun +9 位作者 Kepeng She Mingqi Lv Yiqiao Zhang Yawen Xiao yangkun Liu Changhao Han Xinyue Xu Shuqing Yang Guixue Wang Guangchao Zang 《Regenerative Biomaterials》 SCIE EI CSCD 2023年第1期1356-1371,共16页
The most common socioeconomic healthcare issues in clinical are burns,surgical incisions and other skin injuries.Skin lesion healing can be achieved with nanomedicines and other drug application techniques.This study ... The most common socioeconomic healthcare issues in clinical are burns,surgical incisions and other skin injuries.Skin lesion healing can be achieved with nanomedicines and other drug application techniques.This study developed a nano-spray based on cross-linked amorphous calcium peroxide(CaO_(2))nanoparticles of polyacrylic acid(PAA)for treating skin wounds(PAA-CaO_(2)nanoparticles).CaO_(2)serves as a‘drug’precursor,steadily and continuously releasing calcium ions(Ca2+)and hydrogen peroxide(H2O_(2))under mildly acidic conditions,while PAA-CaO_(2)nanoparticles exhibited good spray behavior in aqueous form.Tests demonstrated that PAA-CaO_(2)nanoparticles exhibited low cytotoxicity and allowed L929 cells proliferation and migration in vitro.The effectiveness of PAA-CaO_(2)nanoparticles in promoting wound healing and inhibiting bacterial growth in vivo was assessed in SD rats using full-thickness skin defect and Staphylococcus aureus(S.aureus)-infected wound models based thereon.The results revealed that PAA-CaO_(2)nanoparticles demonstrated significant advantages in both aspects.Notably,the infected rats’skin defects healed in 12 days.The benefits are linked to the functional role of Ca^(2+)coalesces with H2O_(2)as known antibacterial and healing-promoted agents.Therefore,we developed nanoscale PAA-CaO_(2)sprays to prevent bacterial development and heal skin lesions. 展开更多
关键词 polyacrylic acid calcium peroxide NANOMEDICINES ANTIBACTERIAL wound healing
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Real- and momentum-indirect neutral and charged excitons in a multi-valley semiconductor
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作者 Zhiheng Huang Yuhui Li +20 位作者 Tao Bo Yanchong Zhao Fanfan Wu Lu Li Yalong Yuan Yiru Ji Le Liu Jinpeng Tian Yanbang Chu Xiaozhou Zan Yalin Peng Xiuzhen Li yangkun Zhang Kenji Watanabe Takashi Taniguchi Zhipei Sun Wei Yang Dongxia Shi Shixuan Du Luojun Du Guangyu Zhang 《National Science Open》 2023年第4期76-85,共10页
Excitons dominate the photonic and optoelectronic properties of a material.Although significant advancements exist in understanding various types of excitons,progress on excitons that are indirect in both real-and mom... Excitons dominate the photonic and optoelectronic properties of a material.Although significant advancements exist in understanding various types of excitons,progress on excitons that are indirect in both real-and momentum-spaces is still limited.Here,we demonstrate the real-and momentum-indirect neutral and charged excitons(including their phonon replicas)in a multi-valley semiconductor of bilayer MoS_(2),by performing electric-field/doping-density dependent photoluminescence.Together with first-principles calculations,we uncover that the observed real-and momentum-indirect exciton involves electron/hole from K/Γvalley,solving the longstanding controversy of its momentum origin.Remarkably,the binding energy of real-and momentum-indirect charged exciton is extremely large(i.e.,~59 meV),more than twice that of real-and momentum-direct charged exciton(i.e.,~24 meV).The giant binding energy,along with the electrical tunability and long lifetime,endows real-and momentum-indirect excitons an emerging platform to study many-body physics and to illuminate developments in photonics and optoelectronics. 展开更多
关键词 excitons real-and momentum-indirect exciton giant binding energy electrical tunability multi-valley semiconductor
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HER2 gene status and the relationship with p21 protein expression in gastric cancer 被引量:3
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作者 Yongjie Li yangkun Wang +4 位作者 Xianwei Zhang Fulin Li Nianlong Meng Xutao Yuan Jinsheng Song 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第3期162-165,共4页
Objective: We aimed to analysis the HER2 gene status and its relationship with p21 protein expression in gastric carcinoma. Methods: Fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) techn... Objective: We aimed to analysis the HER2 gene status and its relationship with p21 protein expression in gastric carcinoma. Methods: Fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) techniques were used to detect HER2 gene status and p53 protein in 59 cases of gastric cancer. Results: FISH detection of HER2 gene amplification rate was 16.9% (10/59), HER2 gene amplification in 49 cases without copy number gain and gene amplification were a total of 49.2% (29/59). HER2 protein expression was 42.4% (25/59), HER2 gene amplification rates in patients with +++, ++ HER2 protein expression were 3/3 and 5/8, while in patients with + HER2 protein expression, it was 2/14, there was significant difference (P 0.05). p21 protein expression rate was 49.2% (29/59), HER2 gene amplification rates and p21 protein expression had significant difference in tumor invasion depth, lymph node metastasis (P 0.05); had no statistical significance in histological type, age, gender differences (P 0.05). Conclusion: HER2 gene amplification rate and gene copy number had positively correlation with p21 protein expression, HER2 gene status and expression of p21 protein combined detection can provide a reference value in gastric cancer metastasis, patient’s condition development and prognosis, it also can guide clinical development of individual treatment. 展开更多
关键词 stomach cancer HER2 gene p21 protein expression
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Fuzzy Random Reliability Analysis of Blocky Rock-Mass in Slopes 被引量:3
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作者 yangkun ZHANGXin 《Journal of China University of Mining and Technology》 EI 2005年第2期129-134,共6页
Slope stability assessment is a geotechnical problem characterized by many sources of uncertainty. In clas- sical reliability analysis, only the randomness of uncertainties is taken into account but the fuzziness of t... Slope stability assessment is a geotechnical problem characterized by many sources of uncertainty. In clas- sical reliability analysis, only the randomness of uncertainties is taken into account but the fuzziness of them is ignored. In this paper, a fuzzy probability approach and a fuzzy JC method are presented for the reliability analysis. The two methods have been applied to stability analysis of a certain slope of permanent ship lock in the Three-Gorges Project. The results obtained from these two methods are basically the same. However, compared with the fuzzy probability means, the fuzzy JC method can reflect the real situation better because it uses a fuzzy-based analysis applied to not only limit state equation but also mechanical parameters. 展开更多
关键词 blocky rock mass vector analysis fuzzy-random reliability fuzzy failure probability
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Vibrational characteristics of rotating soft cylinders 被引量:2
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作者 Kecheng Li Yinnan Zhang +2 位作者 Haifei Zhan yangkun Du Chaofeng Li 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2021年第5期34-42,共9页
Rotating structural components are omnipresent in engineering structures and natural world. This work investigates the effects of the centrifugal and Coriolis forces on the free vibrational characteristics of soft cyl... Rotating structural components are omnipresent in engineering structures and natural world. This work investigates the effects of the centrifugal and Coriolis forces on the free vibrational characteristics of soft cylinders rotating with respect to the axis of symmetry based on the nonlinear elasticity and linear incremental theories. The formulations indicate that the biasing deformation, instantaneous elastic moduli, and incremental equations of motion strongly depend on the rotating speed. The characteristic equation for the natural frequency is derived using the state-space method and approximate laminate technique.The numerical examples included in this work demonstrate that the centrifugal and Coriolis forces might have significant effects on the vibrational characteristics of the cylinder. Results of this work will benefit the design and control of novel engineering systems with rotating soft cylinders or shafts. 展开更多
关键词 rotating soft cylinders vibrational characteristics centrifugal force Coriolis force
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Risk Evaluation on Logistics Finance of Agricultural Products Based on Fuzzy-AHP Model 被引量:2
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作者 Yan PANG yangkun XIA 《Asian Agricultural Research》 2015年第9期1-5 8,8,共6页
The development of logistics finance business for agricultural products is the best way to realize the common interests of logistics enterprises,small and medium-sized agricultural product enterprises and financial in... The development of logistics finance business for agricultural products is the best way to realize the common interests of logistics enterprises,small and medium-sized agricultural product enterprises and financial institutions,which will contribute to the development of China's new socialist rural economy and the construction of " two-oriented society". As the agricultural products have some special attributes,it's easy to create the risk in carrying out the logistics finance business. The paper constructs a risk evaluation indicator system for logistics finance of agricultural product,and uses the Fuzzy-AHP model to evaluate. The results show that the comprehensive risk level is normal risk,which shows that third-party logistics enterprises can carry out the logistics financial business of agricultural products,but the risks from logistics enterprises and agricultural collateral need to be prevented. 展开更多
关键词 LOGISTICS FINANCE AGRICULTURAL PRODUCTS RISK evalu
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Modeling on monitoring the growth and rupture assessment of saccular aneurysms 被引量:2
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作者 yangkun Du Chaofeng Lu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2017年第2期117-120,共4页
The unpredictable rupture of saccular aneurysms especially of the intracerebral aneurysm is a knotty problem that always results in high mortality. Traditional diagnosis of medical images, which gives the aneurysm siz... The unpredictable rupture of saccular aneurysms especially of the intracerebral aneurysm is a knotty problem that always results in high mortality. Traditional diagnosis of medical images, which gives the aneurysm size and compares with a speculated critical size from clinical statistics, was demonstrated inadequate to forecasting rupture. Here, we propose a new detecting strategy that uses a dielectric elastomer (DE) capacitance sensor to monitor the growth of saccular aneurysms and deliver both the wall stress and geometric parameters, Based on the elastic growth theory together with the finite deformation analyses, the correlation between the real-time output capacitance of the DE sensor and the wall stress and/or geometry of an aneurysm is derived. Compared to clinic statistics and biomechanics simulations, the wall stress and geometric size may be used as combined indicators to assess the rupture risk of a saccular aneurysm, Numerical results show that an output relative capacitance of 30 indicates a high risk of rupture, Finally, the sensitivity and resolution of the DE sensor are proved adequately high for monitoring the growth state and evaluating the rupture risk of a saccular aneurysm. 展开更多
关键词 Saccular aneurysms Rupture risk Dielectric elastomer capacitance sensor Elastic growth theory Finite deformation
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Diageneses and Their Influences on Reservoir Properties of Chang 2 Oil Member in Renshan Region, Zhidan Oilfield, Ordos Basin 被引量:1
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作者 YANG Kang ZHOU Xue +5 位作者 LI Hong XIE Wei DONG yangkun LIU Yongjie SONG Shijun ZHAO Leizhao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期142-143,共2页
1 Introduction Yanchang Formation in Upper Triassic,Ordos basin contains the most abundant hydrocarbon resources in North China(Wang et al.,2014).The sandstones are the most important oil-bearing reservoirs in Yanchang
关键词 Zhidan Oilfield SEM Ordos Basin Diageneses and Their Influences on Reservoir Properties of Chang 2 Oil Member in Renshan Region
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The new discovery of Oligocene cyprinidae fossil in Qaidam basin, Northwest China
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作者 LIU Yongjie LI Yongxiang +3 位作者 LI Hong NIU Yuanzhe LIU Fan DONG yangkun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期136-137,共2页
1 Introduction Some Cyprinidae fossils have been reported about 420km east of the fossil site in the same period of Wulan Husentu1 layer,and have been used as an important fossil evidence for a deep understanding of the
关键词 The new discovery of Oligocene cyprinidae fossil in Qaidam basin Northwest China length
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Pathological characteristics and immunophenotype analysis of cervical intraepithelial neoplasia
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作者 Yingying Li Sunan Wang +1 位作者 yangkun Wang Xingzhen Zeng 《Oncology and Translational Medicine》 2016年第6期285-289,共5页
Objective To explore the clinical pathological features and immunophenotypes of cervical intraepithelial neoplasia(CIN).Methods The protein expression of p16, p53, Bcl-2, and c-erb B-2 in 59 cases of CIN, 20 cases of ... Objective To explore the clinical pathological features and immunophenotypes of cervical intraepithelial neoplasia(CIN).Methods The protein expression of p16, p53, Bcl-2, and c-erb B-2 in 59 cases of CIN, 20 cases of cervical squamous cell carcinoma, and 20 cases of normal cervical tissues were tested using immunohistochemistry staining.Results The expression rates of p16, p53, Bcl-2, and c-erb B-2 in CIN tissues were 76.3%(45/59), 28.85(17/59), 61.0%(36/59), and 40.0%(23/59), respectively. The expression rates of p16, p53, Bcl-2, and c-erb B-2 in cervical squamous cell carcinoma tissues were 60.0%(12/20), 60.0%(12/20), 75.0%(15/20), and 65.0%(13/20), respectively. The expression rates of p16, p53, Bcl-2, and c-erb B-2 in normal cervical tissues were 0.0%(0/20), 0.0%(0/20), 35.0%(7/20), 0.0%(0/20), respectively. In comparison to normal tissues, the differential expressions of p16, p53, and Bcl-2 in squamous cell carcinoma and CIN were statistically significant(P <0.001), whereas the difference between the squamous cell carcinoma and CIN was not significant(P >0.05). In comparison to normal tissues, the differential expressions of c-erb B-2 and p53 in squamous cell carcinoma and CIN were statistically significant(P >0.05). The differential expressions of Bcl-2, c-erb B-2, and p53 in CIN 3 were statistically significant in comparison to CIN 1 and CIN 2(P <0.05). Conclusion Overexpression of Bcl-2 occurs early in the development of cervical cancer, whereas p16 and c-erb B-2 overexpression are markers for cell malignancy. The expression of p53 is correlated with the development of cervical cancer. 展开更多
关键词 cervical intraepithelial neoplasia clinical pathology PROTEIN IMMUNOHISTOCHEMISTRY
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Periodic-phase-diagram similarity method for weak signal detection
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作者 Ruilan Tian yangkun Zhang +3 位作者 Shaopu Yang Kai Yuan Qiang Xue Quanrong Ren 《International Journal of Mechanical System Dynamics》 2021年第2期248-255,共8页
The periodic-phase-diagram similarity method is proposed to identify the frequency of weak harmonic signals.The key technology is to find a set of optimal coefficients for Duffing system,which leads to the periodic mo... The periodic-phase-diagram similarity method is proposed to identify the frequency of weak harmonic signals.The key technology is to find a set of optimal coefficients for Duffing system,which leads to the periodic motion under the influence of weak signal and strong noise.Introducing the phase diagram similarity,the influences of strong noise on the similarity of periodic phase diagram are discussed.The principle of highest similarity of periodic phase diagram with the same frequency is detected by discussing the persistence of similarity of periodic motion phase diagram under the strong noise and the periodic-phase-diagram similarity method is constructed.The weak signals of early fault and strong noise are input into Duffing system to obtain the identified system.The stochastic subharmonic Melnikov method is extended to obtain the conditions of the optimal coefficients for the identified system.Based on the results,the constructed frequency conversion harmonic weak signals are considered to form a datum periodic system.With the change of frequency in the datum periodic system,the phase diagram similarity of the two constructed systems can be calculated.Based on the periodic-phase-diagram similarity method,the frequency of weak harmonic signals can be identified by the principle of highest similarity of periodic phase diagram with the same frequency.The results of numerical simulation and the early fault diagnosis results of actual bearings verify the feasibility of the periodic-phase-diagram similarity method.The accuracy of the detection effect is 97%,and the minimum signal-to-noise ratio is−80.71 dB. 展开更多
关键词 periodic system signal-to-noise ratio stochastic subharmonic Melnikov method strong noise weak signal
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Incorporating sorption/desorption of organic pollutants into river water quality model
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作者 LOUBao-feng ZHULi-zhong yangkun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期559-563,共5页
Preliminary research was conducted about how to incorporate sorption/desorption of organic pollutants with suspended solids and sediments into single-chemical and one-dimensional water quality model of Jinghang Canal.... Preliminary research was conducted about how to incorporate sorption/desorption of organic pollutants with suspended solids and sediments into single-chemical and one-dimensional water quality model of Jinghang Canal. Sedimentation-resuspension coefficient k 3 was deduced; characteristics of organic pollutants, concentrations and components of suspended solids/sediments and hydrological and hydraulic conditions were integrated into k 3 and further into river water quality model; impact of sorption/desorption of organic pollutants with suspended solids and sediments on prediction function of the model was discussed. Results demonstrated that this impact is pronounced for organic pollutants with relatively large K oc and K ow, especially when they are also conservative and f oc of river suspended solids/sediments is high, and that incorporation of sorption/ desorption of organic pollutants into river water quality model can improve its prediction accuracy. 展开更多
关键词 water quality model sorption/desorption sedimentation-resuspension coefficient
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Atlantis~?T3色谱柱检测保健酒中西地那非和他达拉非的含量
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作者 张建炀 杨坤 唐国芳 《现代食品》 2018年第7期132-137,共6页
目的:建立Waters Atlantis~?T3色谱柱检测保健酒中西地那非和他达拉非含量的液相色谱法。方法:保健酒样品经乙腈涡旋混合提取,Atlantis~?T3色谱柱分离,以甲醇-10 mmol/L乙酸铵溶液为流动相进行梯度洗脱,流速为1.0 m L/min,进样量为10μL... 目的:建立Waters Atlantis~?T3色谱柱检测保健酒中西地那非和他达拉非含量的液相色谱法。方法:保健酒样品经乙腈涡旋混合提取,Atlantis~?T3色谱柱分离,以甲醇-10 mmol/L乙酸铵溶液为流动相进行梯度洗脱,流速为1.0 m L/min,进样量为10μL,波长为230 nm,采用DAD光谱图进行定性,外标法定量。结果:西地那非和他达拉非在0.2~20μg/m L范围内线性关系良好,线性相关系数R均大于0.999;西地那非的检出限为0.82 mg/kg,他达拉非的检出限为0.94 mg/kg;西地那非在0.1、0.3和0.5 mg/kg水平上的加标回收率为96.0%~102.0%,他达拉非在0.1、0.3和0.5 mg/kg水平上的加标回收率为90.0%~96.6%,西地那非的相对标准偏差为0.11%~0.41%,他达拉非的相对标准偏差为0.11%~0.37%。结论:本方法操作简便、快速、灵敏度高、重复性好,可用于保健酒中西地那非和他达拉非的含量测定。 展开更多
关键词 保健酒 西地那非 他达拉非
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Clinicopathologic features and immunohistochemical analysis of 67 gastric adenoma patients
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作者 Xiuli Wang yangkun Wang Yingchao Wu Xuexia Lv Nianlong Meng Jian Yin Xutao Yuan 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第9期511-515,共5页
Objective: The aim of this study was to investigate the clinicopathologic features of gastric adenoma. Methods: Sixty-seven cases of adenoma diagnosis of gastric biopsy specimens using light microscopy, immunohistoc... Objective: The aim of this study was to investigate the clinicopathologic features of gastric adenoma. Methods: Sixty-seven cases of adenoma diagnosis of gastric biopsy specimens using light microscopy, immunohistochemistry, and follow-up methods were studied. Results: Histopathology of gastric adenoma characteristics: nuclear anaplasia, showing increase of nuclear volume and irregular, and the emergence of one or more nucleoli, mitotic ≤ 2/10 high power field (HPF). Structural changes in the gland: adenoma of the duct much more consistent, sometimes the size of the gland and irregular contour, might be associated with intestinal metaplasia. Increased significantly when the nuclear volume, mitotic 〉 2/10 HPF, irregular gland distortion, branched structures, suggesting the development of adenomas. Immunophenotype: tumor-associated carbohydrate antigens had a higher expression; adenomatous polyposis coli gene (APC) and carcinoembryonic antigen (CEA) expression of closely related with the formation of adenoma. Mucin muc-2 high expression was negatively correlated with muc-1 low expression, the combination of both can help to determine the development and changes in gastric adenoma. Survivin, Bcl-2, p21 and p53 protein expression rare cases, four were combined with the malignant transformation of gastric adenoma was important discriminant. Ki-67 positive cells 20%-40%, and could be used as degree of cell proliferation, a reference indicator of prognosis. Thirty-six to 49 months of follow-up results showed that cured 44.8% (30/67), there adenomatous hyperplasia 35.8% (24167), with the development of dysplasia showed 14.4% (11/67), the development of intramucosal carci- noma were 3.0% (2/67). Conclusion: Gastric adenomas occur significantly increased nuclear volume, mitotic 〉 2/10 HPF, ir- regular gland distortion, branch-like structure; immunohistochemical staining showed positive expression of muc-2 decreased, muc-1 positive expression; cell proliferation index Ki -67 � 展开更多
关键词 gastric biopsy ADENOMA PATHOLOGY IMMUNOHISTOCHEMISTRY
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Study on the protein expression and amplification of HER2 gene in gastric cancer
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作者 Sunan Wang Yingying Li +4 位作者 Zhengshun Xu Wenzhao Zhao Tian Yun Wuling Zhu yangkun Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第6期267-272,共6页
Objective: The aim of the study was to investigate the human epidermal growth factor receptor 2(HER2) gene amplification and protein expression and interpretation points in the stomach mixed carcinomas. Methods: Immun... Objective: The aim of the study was to investigate the human epidermal growth factor receptor 2(HER2) gene amplification and protein expression and interpretation points in the stomach mixed carcinomas. Methods: Immunohistochemistry(IHC) and fluorescence in situ hybridization(FISH) technique were used to detect HER2 gene amplification and expression of HER2 protein in 442 cases of gastric mixed carcinoma. Results: The expression rate of HER2 protein was 41.2%(182/442): the HER2 protein expression IHC 3+ extensive type in 18 cases, partial type in 21 cases, focal type in 8 cases, accounting for 10.6%(47/442); the HER2 protein expression IHC 2+ extensive type in 23 cases, partial type in 28 cases, focal type in 11 cases, accounting for 14.0%(62/442); the HER2 protein expression IHC 1+ extensive type in 27 cases, partial type in 31 cases, focal type in 15 cases, accounting for 16.5%(73/442). HER2 gene amplification rate of 442 cases was 16.1%(71/442). In 182 cases of HER2 protein positive expression, the HER2 gene cluster amplification rate was 14.8%(27/182), large granular amplification rate 11.0%(20/182), punctate amplification rate 6.0%(11/182) and high polysomy 7.1%(13/182). In 71 cases of HER2 gene amplification, there was 42 cases of HER2 protein expression IHC 3+, 22 cases of HER2 protein expression IHC 2+, and 7 cases of IHC 1+. Conclusion: HER2 detection of gastric mixed carcinoma has great heterogeneity, HER2 protein positive expression is divided into extensive type, partial type and focal type, and HER2 gene positive amplification is divided into cluster amplification, large granular amplification, punctate amplification and high polysomy. These typing of HER2 protein expression and HER2 gene amplification provide reference index to quantify for targeted therapeutic effect of anticancer drugs. 展开更多
关键词 stomach neoplasms mixed tumor human epidermal growth factor receptor 2 (HER2) gene HER2 proteinfluorescence in situ hybridization (FISH) immunohistochemistry (IHC)
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世界稀土资源现状 被引量:47
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作者 张博 宁阳坤 +1 位作者 曹飞 杨卉芃 《矿产综合利用》 CAS 北大核心 2018年第4期7-12,共6页
稀土由于其特有的物理化学性质被广泛应用于现代工业的各个方面,并将在未来工业体系中发挥着越来越重要的作用。本文首先对稀土的性质以及主要矿物和矿床类型进行了介绍;然后分析了全球稀土矿资源概况,整体上看全球稀土资源非常集中地... 稀土由于其特有的物理化学性质被广泛应用于现代工业的各个方面,并将在未来工业体系中发挥着越来越重要的作用。本文首先对稀土的性质以及主要矿物和矿床类型进行了介绍;然后分析了全球稀土矿资源概况,整体上看全球稀土资源非常集中地分布在几个稀土资源大国的大型、超大型稀土矿床;最后,文章对全球稀土矿资源的开发利用趋势、价格变化进行了分析,结果表明近年来随着中国一系列稀土管制政策的实行和稀土价格的增长,各国新开稀土矿山数量和稀土产量均有明显增加,世界稀土生产依赖中国单边供应的局面将会改变;随着稀土在高新技术领域的广泛应用,稀土需求量特别是重稀土需求量将会急剧增加。 展开更多
关键词 稀土资源 储量 产量 矿山 矿床
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