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Effects of heavy metal pollution on farmland soils and crops:A case study of the Xiaoqinling Gold Belt,China 被引量:27
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作者 Rui-ping Liu You-ning Xu +2 位作者 Jiang-hua Zhang Wen-ke Wang Rafaey M Elwardany 《China Geology》 2020年第3期402-410,共9页
This paper focuses on the heavy metal enrichment and heavy metal pollution degree associated with mining activities in some crops and the soils of different parent materials in the Xiaoqinling Gold Belt.According to t... This paper focuses on the heavy metal enrichment and heavy metal pollution degree associated with mining activities in some crops and the soils of different parent materials in the Xiaoqinling Gold Belt.According to the geochemical analysis results of the soils observed in the gold belt,the soils are most highly enriched in Pb,followed by Cr,Cu,and Zn.Furthermore,they are relatively poor in Hg,Cd,and As.It is also shown that the heavy metals in all kinds of soils have the same geochemical characteristics in the gold belt.As for the crops(such as corn and wheat)in the gold belt,Zn and Cu are the most abundant elements,followed by Pb and Cr.Meanwhile,Hg,Cd,and As were found to have relatively low concentrations in the crops.The heavy metals in wheat and corn have the same geochemical characteristics in the gold belt in general.Compared to the aeolian loess soils and the crops therein,heavy metals are more enriched in diluvial and alluvial soils and the crops therein.As shown by relevant studies,the Hg,Pb,Cd,Cu,and Zn pollution are mainly caused by mining activities.Corn and wheat in the gold belt have a high tendency of risk exposure to heavy metal pollution since they are mostly affected by mining activities and feature high background values of heavy metal concentrations.Furthermore,wheat is more liable to be enriched in heavy metals than corn is grown in all types of soils.The Hg pollution in soils leads to Hg accumulation,increasing the risk of Hg uptake in crops,and further affecting human health.This study will provide a scientific basis for the control and management of heavy metals in farmland soils of mining areas. 展开更多
关键词 Heavy metal pollution CROPS FARMLAND Environmental investigation engineering of soil Xiaoqinling Gold Belt China
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Vertically Aligned Silicon Carbide Nanowires/Boron Nitride Cellulose Aerogel Networks Enhanced Thermal Conductivity and Electromagnetic Absorbing of Epoxy Composites 被引量:22
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作者 Duo Pan Gui Yang +11 位作者 Hala MAbo-Dief Jingwen Dong Fengmei Su Chuntai Liu Yifan Li Ben Bin Xu Vignesh Murugadoss Nithesh Naik Salah MEl-Bahy Zeinhom MEl-Bahy Minan Huang Zhanhu Guo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第7期209-227,共19页
With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel(CA) with highly enhanced thermal conductivity(TC) in vertical... With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel(CA) with highly enhanced thermal conductivity(TC) in vertical planes was successfully obtained by constructing a vertically aligned silicon carbide nanowires(SiC NWs)/boron nitride(BN) network via the ice template-assisted strategy. The unique network structure of SiC NWs connected to BN ensures that the TC of the composite in the vertical direction reaches 2.21 W m^(-1) K^(-1) at a low hybrid filler loading of 16.69 wt%, which was increased by 890% compared to pure epoxy(EP). In addition, relying on unique porous network structure of CA, EP-based composite also showed higher TC than other comparative samples in the horizontal direction. Meanwhile, the composite exhibits good electrically insulating with a volume electrical resistivity about 2.35 × 10^(11) Ω cm and displays excellent electromagnetic wave absorption performance with a minimum reflection loss of-21.5 dB and a wide effective absorption bandwidth(<-10 dB) from 8.8 to 11.6 GHz. Therefore, this work provides a new strategy for manufacturing polymer-based composites with excellent multifunctional performances in microelectronic packaging applications. 展开更多
关键词 EPOXY Ice template Vertical alignment Thermal conductivity Multifunctionality
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An overview of occult hepatitis B virus infection 被引量:22
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作者 Zeinab Nabil Ahmed Said 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第15期1927-1938,共12页
Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replic... Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome. 展开更多
关键词 Hepatitis B virus Occult infection Occult hepatitis B virus infection Occult hepatitis B Chronic liver disease Hepatocellular carcinoma Hepatitis B surface antigen
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Early diagnostic evaluation of miR-122 and miR-224 as biomarkers for hepatocellular carcinoma 被引量:20
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作者 Khalda S.Amr Hanan Abd Elmawgoud Atia +1 位作者 Rehab Abd Elazeem Elbnhawy Wafaa M.Ezzat 《Genes & Diseases》 SCIE 2017年第4期215-221,共7页
Hepatocellular carcinoma(HCC)is one of the common lethal types of tumor all over the world.The lethality of HCC accounts for many reasons.One of them,the lack of reliable diagnostic markers at the early stage,in this ... Hepatocellular carcinoma(HCC)is one of the common lethal types of tumor all over the world.The lethality of HCC accounts for many reasons.One of them,the lack of reliable diagnostic markers at the early stage,in this context,serum miRNAs became promising diagnostic biomarkers.Herein,we aimed to identify the predictive value of two miRNAs(miR-122 and miR-224)in plasma of patients with HCC preceded by chronic HCV infection.Taqman miRNA assays specific for hsa-miR-122 and hsa-miR-224 were used to assess the expression levels of the chosen miRNAs in plasma samples collected from three groups;40 patients with HCC related to HCV,40 with CHC patients and 20 healthy volunteers.This study revealed that the mean plasma values of miRNA-122 were significantly lower among HCC group when compared to CHC and control groups(P<0.001).Whereas,miR-224 mean plasma values were significantly higher among HCC group when compared to both CHC group and control group.Moreover,it was found that miR-122 can predict development of HCC at cut-off value<0.67(RQ)and(AUC Z 0.98,P<0.001).As regards miR-224,it can predict development of HCC at cut-off value>1.2(RQ)and(AUC Z 0.93,P<0.001),while the accuracy of AFP to diagnose HCC was(AUC:0.619;P Z 0.06).In conclusion,the expression plasma of miR-122 and miR-224 could be used as noninvasive biomarkers for the early prediction of developing HCC at the early stage. 展开更多
关键词 DIAGNOSIS Hepatocellular carcinoma MIR-122 miR-224 Sensitivity
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基于纳米压痕技术的破碎煤样力学特性实验研究 被引量:19
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作者 孙长伦 李桂臣 +2 位作者 GOMAH Mohamed Elgharib 许嘉徽 荣浩宇 《煤炭学报》 EI CAS CSCD 北大核心 2020年第S02期682-691,共10页
在煤系地层中,与完整坚硬岩石不同,煤体松软破碎、强度低。受地应力和开采扰动的影响,松软破碎煤体内部裂隙进一步发育,强度进一步弱化,很难获得标准的完整煤样进行常规的拉压剪力学测试。煤体力学参数的缺失增加了采煤、掘进、支护和... 在煤系地层中,与完整坚硬岩石不同,煤体松软破碎、强度低。受地应力和开采扰动的影响,松软破碎煤体内部裂隙进一步发育,强度进一步弱化,很难获得标准的完整煤样进行常规的拉压剪力学测试。煤体力学参数的缺失增加了采煤、掘进、支护和瓦斯抽采等采矿活动的风险。因此,探究新的力学实验方法对于煤矿生产活动非常有必要。文章采用纳米压痕技术测试破碎煤体的硬度、弹性模量和断裂韧度,分析了不同力学参数之间的联系。纳米压痕实验设计4个峰值荷载,每个峰值荷载进行12次实验,阐述了煤的力学特性与峰值荷载之间的关系。结合X射线衍射和扫描电镜实验,讨论了煤样矿物组分对其力学性质的影响规律。实验结果表明,峰值荷载在1~30 mN,煤的硬度和弹性模量不随峰值荷载的增加而明显变化;然而,煤的断裂韧度随峰值荷载的增加有增大的趋势。峰值荷载为1,5,10和30 mN时,煤的平均断裂韧度为0.40,0.36,0.61和0.77 MPa·m0.5。煤的纳米压痕硬度、弹性模量和断裂韧度具有明显的线性关系。硬度和弹性模量之间的线性关系与峰值荷载无关;断裂韧度与弹性模量之间的线性关系受峰值荷载的影响。煤是以有机质为基体的非均质岩土材料,其力学性质和矿物组分密切相关。石英强度高,能够强化煤基质的力学特性;高岭石松软,使煤具有软弱大变形特性。采用纳米压痕技术研究破碎煤体力学特性,具有操作方便,数据可靠和测试精确的优点。 展开更多
关键词 破碎煤样 纳米压痕 力学特性 峰值荷载 矿物组分
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The micropolar fluid model for blood flow through a tapered artery with a stenosis 被引量:15
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作者 Kh.S.Mekheimer M.A.El Kot 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第6期637-644,共8页
A micropolar model for axisymmetric blood flow through an axially nonsymmetreic but radially symmetric mild stenosis tapered artery is presented. To estimate the effect of the stenosis shape, a suitable geometry has b... A micropolar model for axisymmetric blood flow through an axially nonsymmetreic but radially symmetric mild stenosis tapered artery is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the axial shape of the stenosis can be changed easily just by varying a parameter (referred to as the shape parameter). The model is also used to study the effect of the taper angle Ф. Flow parameters such as the velocity, the resistance to flow (the resistance impedance), the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis (stenosis throat) have been computed for different values of the shape parameter n, the taper angle Ф, the coupling number N and the micropolar parameter m. It is shown that the resistance to flow decreases with increasing the shape parameter n and the micropolar parameter m while it increases with increasing the coupling number N. So, the magnitude of the resistance impedance is higher for a micropolar fluid than that for a Newtonian fluid model. Finally, the velocity profile, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis are discussed for different values of the parameters involved on the problem. 展开更多
关键词 Micropolar fluid Blood flow Tapered artery
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Creep characteristics of coal and rock investigated by nanoindentation 被引量:14
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作者 Changlun Sun Guichen Li +2 位作者 Mohamed Elgharib Gomah Jiahui Xu Yuantian Sun 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期769-776,共8页
In coal mining industry,with the depth growing of coal mines,the creep behaviours of coal and rock can extensively affect the mining safety,coalbed methane recovery and geo-sequestration.To acquire a better insight in... In coal mining industry,with the depth growing of coal mines,the creep behaviours of coal and rock can extensively affect the mining safety,coalbed methane recovery and geo-sequestration.To acquire a better insight into their creep characteristics,an efficient and robust researching technique,nanoindentation,was applied to investigate the creep performances of coal and rock samples obtained from two coal mines in the east of China.Creep characteristics were reflected by evaluating the curves of creep depth versus creep time of nanoindentation tests during the load-holding period at the peak load of 30 mN.These curves can be divided into two stages:transient stage and steady stage;and the time of load-holding period of 5 s,which is the dividing point between two stages,can efficiently avoid the influence of creep displacement on the unloading curves.The exponential function can perfectly fit creep curves and Kelvin model can be used to calculate the rheological parameters of coal and rock samples.Calculated results yield values for the creep modulus and viscosity terms of coal and rock.This study also settled a particular emphasis on the selection of the positions of indentations to obtain the rheological properties of mineralogical constituents in heterogonous coal and rock samples and their elastic aftereffect. 展开更多
关键词 Coal and rock NANOINDENTATION CREEP Heterogeneous properties Elastic aftereffect
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Medical management of patients after bariatric surgery: Principles and guidelines 被引量:10
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作者 Abd Elrazek Mohammad Ali Abd Elrazek Abduh Elsayed Mohamed Elbanna Shymaa E Bilasy 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2014年第11期220-228,共9页
Obesity is a major and growing health care concern. Large epidemiologic studies that evaluated the relationship between obesity and mortality, observed that a higher body-mass index(BMI) is associated with increased r... Obesity is a major and growing health care concern. Large epidemiologic studies that evaluated the relationship between obesity and mortality, observed that a higher body-mass index(BMI) is associated with increased rate of death from several causes, among them cardiovascular disease; which is particularly true for those with morbid obesity. Being overweight was also associated with decreased survival in several studies. Unfortunately, obese subjects are often exposed to public disapproval because of their fatness which significantly affects their psychosocial behavior. All obese patients(BMI ≥ 30 kg/m2) should receive counseling on diet, lifestyle, exercise and goals for weight management. Individuals with BMI ≥ 40 kg/m2 and those with BMI > 35 kg/m2 with obesity-related comorbidities; who failed diet, exercise, and drug therapy, should be considered for bariatric surgery. In current review article, we will shed light on important medical principles that each surgeon/gastroenterologist needs to know about bariatric surgical procedure, with special concern to the early post operative period. Additionally, we will explain the common complications that usually follow bariatric surgery and elucidate medical guidelines in their management. For the first 24 h after the bariatric surgery, the postoperative priorities include pain management, leakage, nausea and vomiting, intravenous fluid management, pulmonary hygiene, and ambulation. Patients maintain a low calorie liquid diet for the first few postoperative days that is gradually changed to soft solid food diet within two or three weeks following the bariatric surgery. Later, patients should be monitored for postoperative complications. Hypertension, diabetes, dumping syndrome, gastrointestinal and psychosomatic disorders are among the most important medical conditions discussed in this review. 展开更多
关键词 OBESITY BARIATRIC surgery POSTOPERATIVE CARE BODY-MASS index El banna
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Surgical Outcome of Fusion in Recurrent Lumbar Disc Herniation 被引量:13
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作者 Ahmed Taha Mohamed Youssef 《Open Journal of Modern Neurosurgery》 2020年第1期157-166,共10页
Background Data: Recurrent lumbar disc herniation means re-herniation of disc on the same site and at the same level where a previous discectomy had been performed: recurrent lumbar disc herniation occurs in 7% to 24%... Background Data: Recurrent lumbar disc herniation means re-herniation of disc on the same site and at the same level where a previous discectomy had been performed: recurrent lumbar disc herniation occurs in 7% to 24% of patient underwent discectomy. Tow mean surgical options after reherniated lumbar disc are revision discectomy alone or revision discectomy with fusion discectomy alone in recurrent lumbar disc herniation may not be an efficient treatment without fusion. Objective: To evaluate the efficacy and safety of revision discectomy with fusion in management of recurrent lumbar disc. Study Design: Retrospective study reviewed all patient underwent revision discectomy with fusion, they were 40 patients operated for recurrent lumbar disc from September 2014 to April 2018 in Al-Azhar University Hospital Damietta. Pre- and post-operative data collection and analysis of the outcome were completed based on the “Japanese Orthopedic Association score” (JOAs), and radiographic follow-up. Patients and Methods: 40 patients (30 male and 10 female) underwent revision discectomy with fusion as surgical management for reherniated lumbar disc from September 2014 to April 2018. All patients presented with low back pain and radicular pain with mean duration of 18 months. The patients were investigated by standard plain X-ray CT SCAN and MRI of the lumbar spine. All patients had a discectomy and postero-lateral fusion in revision surgery. These patients followed post operatively clinically for improving pain and neural function, and radiologically for disc removal stability and fusion. Results: The age ranged from 30 to 60 years, mean age was 45 years, male to female ratio 3:1. Follow-up ranged from 18 - 30 months with a mean follow-up 24 months. 30 patients had an excellent outcome, 6 patients had a good outcome, 2 patients had a fair outcome, and 2 patients had a poor outcome. Conclusion: Recurrent lumbar disc herniation occurs in 7% to 24% of patient underwent discectomy. Revision surgery when indicated can be done by 展开更多
关键词 Reherniated LUMBAR DISC Postero-Lateral FUSION REVISION DISCECTOMY
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Microplastic pollution in surface water and sediments of Qinghai-Tibet Plateau: Current status and causes 被引量:12
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作者 Rui-ping Liu Ying Dong +3 位作者 Guo-cang Quan Hua Zhu You-ning Xua Rafaey M.Elwardany 《China Geology》 2021年第1期178-184,共7页
To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-T... To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as follows.First,the average microplastic abundance in surface water of the independent rivers and the whole area is 247−2686 items/m^(3) and 856 items/m^(3),respectively.The average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0−933 items/m^(2) and 362 items/m^(2),respectively.Meanwhile,the degree of microplastic pollution in river sediments is higher than that in lake sediments,and the rivers suffering from microplastic pollution mainly include the Brahmaputra River,Tongtian River,and Nujiang River.Second,compared with the microplastic pollution in other areas of the world,the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human activities.Finally,this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment. 展开更多
关键词 Microplastic pollution Microplastic abundance Surface water River sediment Water environment Human activities Qinghai-Tibet Plateau China
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Graphene oxide-based hydrogels as a nanocarrier for anticancer drug delivery 被引量:10
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作者 Abdullah A.Ghawanmeh Gomaa A.M.Ali +2 位作者 H.Algarni Shaheen M.Sarkar Kwok Feng Chong 《Nano Research》 SCIE EI CAS CSCD 2019年第5期973-990,共18页
Graphene oxide (GO) possesses excellent mechanical strength,biocompatibility,colloidal stability,large surface area and high adsorption capability.It has driven to cancer nanotechnology to defeat cancer therapy obstac... Graphene oxide (GO) possesses excellent mechanical strength,biocompatibility,colloidal stability,large surface area and high adsorption capability.It has driven to cancer nanotechnology to defeat cancer therapy obstacles,via integration into three-dimensional (3D) hydrogel network with biocompatible polymers as nanocomposites carrier,and controllable release of anticancer drugs.Specifically,the surface of GO affords π-π stacking and hydrophilic interactions with anticancer drugs.Additionally,modification of GO with various polymers such as natural and synthetic polymers enhances its biodegradability,drug loading,and target delivery.In this review,GO based hydrogels research accomplishments are reviewed on the aspects of crosslinking strategies,preparation methods,the model drug,polymer conjugation and modification with targeting ligands.Moreover,swelling kinetics,drug release profile and biological activity in vivo and in vitro are discussed.The biocompatibility of GO based hydrogels is also discussed from the perspective of its nano-bio interfaces.Apart from that,the clinical potential of GO based hydrogels and its major challenges are addressed in detail.Finally,this review concludes with a summary and invigorating future perspectives of GO based hydrogels for anticancer drug delivery.It is anticipated that this review can stimulate a new research gateway to facilitate the development of anticancer drug delivery by harnessing the unique properties of GO based hydrogels,such as large surface area,chemical purity,high loading capacity of drug,chemical stability,and the nature of lipophilic for cell membrane penetration. 展开更多
关键词 graphe ne oxide cancer nan otechnology HYDROGEL NANOCARRIER drug delivery
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Simultaneous effects of magnetic field and space porosity on compressible Maxwell fluid transport induced by a surface acoustic wave in a microchannel 被引量:9
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作者 Khaled S.Mekheimer Soliman R.Komy Sara I.Abdelsalam 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期323-332,共10页
Peristaltic motion induced by a surface acoustic wave of a viscous, compressible and electrically conducting Maxwell fluid in a confined parallel-plane microchannel through a porous medium is investigated in the prese... Peristaltic motion induced by a surface acoustic wave of a viscous, compressible and electrically conducting Maxwell fluid in a confined parallel-plane microchannel through a porous medium is investigated in the presence of a constant magnetic field. The slip velocity is considered and the problem is discussed only for the free pumping case. A perturbation technique is employed to analyze the problem in terms of a small amplitude ratio. The phenomenon of a “backward flow” is found to exist in the center and at the boundaries of the channel. In the second order approximation, the net axial velocity is calculated for various values of the fluid parameters. Finally, the effects of the parameters of interest on the mean axial velocity, the reversal flow, and the perturbation function are discussed and shown graphically. We find that in the non-Newtonian regime, there is a possibility of a fluid flow in the direction opposite to the propagation of the traveling wave. This work is the most general model of peristalsis created to date with wide-ranging applications in biological, geophysical and industrial fluid dynamics. 展开更多
关键词 peristaltic flow Maxwell fluid porous medium slip flow microchannel
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Effect of Zn/Mg ratio on cathodic protection of carbon steel using Al-Zn-Mg sacrificial anodes 被引量:9
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作者 Mosaad SADAWY Saad SAAD Randa ABDEL-KARIM 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第8期2067-2078,共12页
Al-Zn-Mg alloys with different Zn/Mg mass ratios were evaluated as sacrificial anodes for cathodic protection of carbon steel in 3.5 wt.%Na Cl solution.The anodes were fabricated from pure Al,Zn and Mg metals using ca... Al-Zn-Mg alloys with different Zn/Mg mass ratios were evaluated as sacrificial anodes for cathodic protection of carbon steel in 3.5 wt.%Na Cl solution.The anodes were fabricated from pure Al,Zn and Mg metals using casting technique.Optical microscopy,SEM-EDS,XRD and electrochemical techniques were used.The results indicated that with decreasing Zn/Mg mass ratio,the grain size ofα(Al)and the particle size of the precipitates decreased while the volume fraction of the precipitates increased.The anode with Zn/Mg mass ratio>4.0 exhibited the lowest corrosion rate,while the anode with Zn/Mg mass ratio<0.62 gave the highest corrosion rate and provided the highest cathodic protection efficiency for carbon steel(AISI 1018).Furthermore,the results showed that the anode with Zn/Mg mass ratio<0.62 exhibited a porous corrosion product compared to the other anodes. 展开更多
关键词 cathodic protection Al-Zn-Mg sacrificial anode current capacity passive film PRECIPITATE grain size
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Influence of magnetic field and Hall currents on blood flow through a stenotic artery 被引量:9
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作者 Kh.S.Mekheimer M.A.El Kot 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第8期1093-1104,共12页
A micropolar model for blood simulating magnetohydrodynamic flow through a horizontally nonsymmetric but vertically symmetric artery with a mild stenosis is presented. To estimate the effect of the stenosis shape, a s... A micropolar model for blood simulating magnetohydrodynamic flow through a horizontally nonsymmetric but vertically symmetric artery with a mild stenosis is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the horizontal shape of the stenosis can easily be changed just by varying a parameter referred to as the shape parameter. Flow parameters, such as velocity, the resistance to flow (the resistance impedance), the wall shear stress distribution in the stenotic region, and its magnitude at the maximum height of the stenosis (stenosis throat), have been computed for different shape parameters, the Hartmann number and the Hall parameter. This shows that the resistance to flow decreases with the increasing values of the parameter determining the stenosis shape and the Hail parameter, while it increases with the increasing Hartmann number. The wall shear stress and the shearing stress on the wall at the maximum height of the stenosis possess an inverse characteristic to the resistance to flow with respect to any given value of the Hartmann number and the Hall parameter. Finally, the effect of the Hartmann number and the Hall parameter on the horizontal velocity is examined. 展开更多
关键词 stenotic artery Hall currents blood flow
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Microplastic pollution in Yellow River,China:Current status and research progress of biotoxicological effects 被引量:8
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作者 Rui-ping Liu Zhi-zhong Li +4 位作者 Fei Liu Ying Dong Jian-gang Jiao Ping-ping Sun El-Wardany RM 《China Geology》 2021年第4期585-592,共8页
This study aims to comprehensively assess the environmental risks of microplastics in the Yellow River,achieving the following results through comprehensive research.The average microplastic abundances in the river wa... This study aims to comprehensively assess the environmental risks of microplastics in the Yellow River,achieving the following results through comprehensive research.The average microplastic abundances in the river waters and sediments are 5358-654000 n/m3 and 43.57-615 items/kg,respectively,and there are fewer microplastics in water samples than in sediments.Microplastics in the study area can be divided into five types according to their occurrence morphologies,namely fragments,foams,films,fibers,and particles.The most widely distributed pollution types in sediments include debris,fibers,and particles.In contrast,fibers are the dominant type in water samples,accounting for 68.18%‒98.93%.The chemical components of the microplastics include polyethylene,polypropylene,polystyrene,polyethylene terephthalate,and polyvinyl chloride.The microplastics are in four colors,with white accounting for a higher proportion.The grain size of the microplastics in tributaries or lakes of the Yellow River is less than 2 mm,which makes them liable to enter organisms for enrichment.Furthermore,the sources of the microplastics are closely related to agricultural and industrial production and biological activities in habitats and exhibit seasonal and hydrological characteristics.The microplastics in the study area show the adsorption of metals and nonmetals to different degrees,which increases the pollution risks of heavy metals combined with microplastics.In addition,microplastics can accumulate in organisms in the Yellow River and cause physical,biochemical,and other damage to aquatic organisms,thus further posing carcinogenic risks to human beings.Therefore,it is necessary to study,monitor,and control the pollution and effects of microplastics in the Yellow River,in order to provide theoretical references for the control of pollution and ecological risk of microplastics in the river. 展开更多
关键词 Microplastic pollution Influence factor Biotoxicological effects Hydrogeological engineering Ecological engineering Yellow River China
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Highly transmitted silver nanowires-SWCNTs conductive flexible film by nested density structure and aluminum-doped zinc oxide capping layer for flexible amorphous silicon solar cells 被引量:7
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作者 Shunliang Gao Xiaohui Zhao +13 位作者 Qi Fu Tianchi Zhang Jun Zhu Fuhua Hou Jian Ni Chengjun Zhu Tiantian Li Yanlai Wang Vignesh Murugadoss Gaber A.M.Mersal Mohamed M.Ibrahim Zeinhom M.El-Bahy Mina Huang Zhanhu Guo 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第31期152-160,共9页
Indium tin oxide(ITO)is widely used in transparent conductive films(TCFs);however,several disadvan-tages,such as high cost and toxicity of indium,limit its applications.Therefore,it is necessary to develop other mater... Indium tin oxide(ITO)is widely used in transparent conductive films(TCFs);however,several disadvan-tages,such as high cost and toxicity of indium,limit its applications.Therefore,it is necessary to develop other materials that can replace ITO.Silver nanowires or single walled carbon nanotubes(SWCNTs)have attracted considerable interest owing to their unique electrical,optical,and thermal stabilities,and thus,they are ideal for transparent electrodes for flexible or stretchable devices.In this study,we develop a novel architecture of composite TCFs on a polyethylene naphthalate(PEN)flexible substrate.Herein,the silver nanowires-SWCNTs films with nested density structure were fabricated through ultrasonic spraying technology by varying the spraying width.For achieving enhanced transmittance,we combined the larger irregular grids and holes with fewer nanowires stacked in the longitudinal direction,more optical chan-nels,and good carrier transport.Thereafter,aluminum-doped zinc oxide(AZO)was used as capping to the structure for enhancing the optical properties of the TCFs.The silver nanowires-SWCNTs/AZO(ASA)bilayer was obtained in the optimized architecture,which showed superior optoelectronic performance to that shown by commercial ITO with a high optical transmittance of 92%at the wavelength of 550 nm and low sheet resistance of 17/sq.In the specially structured conductive film,the significant improvement in the transmittance and uniformity of the sheet resistance was attributed to the effective nanowire junc-tion contact compared to that in ordinary structure of silver nanowires,which reduced the mean density of small clusters of nanowires.Compared with the silver nanowires-SWCNTs films,the ASA bilayer film exhibited excellent resistance to boiling,mechanical bending(10,000 cycles),and CO_(2)plasma.Moreover,the sheet resistance of ASA changed slightly after the tape tests,thereby illustrating a strong adhesion to the PEN substrate after the enclosure of AZO.Meanwhile,the AZO capping layer can enhance the op-tical 展开更多
关键词 Silver nanowires-SWCNTs Nested density TCFs Flexible substrate Photovoltaic devices
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Molecular detection of monocyte chemotactic protein-1 polymorphism in spontaneous bacterial peritonitis patients 被引量:7
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作者 Maysa Kamal Salama Dina Sabry +8 位作者 Mohamed AS Al-Ghussein Rasha Ahmed Sayed AbdAllah Fatma Mohamed Taha Wael Fathy Miriam Safwat Wadie Mona Nabih Amr Abul-Fotouh Tarneem Darwish 《World Journal of Gastroenterology》 SCIE CAS 2014年第33期11793-11799,共7页
AIM: To investigate the association of the functional monocyte chemotactic protein-1 (MCP-1) promoter polymorphism (A-2518G) with spontaneous bacterial peritonitis (SBP).
关键词 Monocyte chemotactic protein-1 GENOTYPE Spontaneous bacterial peritonitis Liver cirrhosis As-cites Gene expression INTERLEUKIN-10
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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
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作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
Role of macroscopic on-site evaluation of endoscopic ultrasoundguided fine-needle aspiration/biopsy:Results of a multicentric prospective study
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作者 Hussein H Okasha Hiwa A Hussein +24 位作者 Khaled M Ragab Omar Abdallah Fedoua Rouibaa Borahma Mohamed Fahd Ghalim Mahmoud Farouk Mohamed Lasheen Mohamed A Elbasiony Ahmed E Alzamzamy Ahmed El Deeb Hassan Atalla Mahmoud El-Ansary Sahar Mohamed Moaz Elshair Wafaa Khannoussi Mohamed Z Abu-Amer Amine Elmekkaoui Mohammed S Naguib Adil Ait Errami Ahmed El-Meligui Ahmed H El-Habashi Mahmoud G Ameen Dalia Abdelfatah Mona Kaddah Hanane Delsa 《World Journal of Gastrointestinal Endoscopy》 2024年第11期595-606,共12页
BACKGROUND The concept of macroscopic on-site evaluation(MOSE)was introduced in 2015 when the endoscopist observed better diagnostic yield when the macroscopically visible core on MOSE was superior to 4 mm.Recent stud... BACKGROUND The concept of macroscopic on-site evaluation(MOSE)was introduced in 2015 when the endoscopist observed better diagnostic yield when the macroscopically visible core on MOSE was superior to 4 mm.Recent studies suggest that MOSE by the endoscopist may be an excellent alternative to rapid on-site evaluation,and some classi-fications have been published.Few studies have assessed the adequacy of histologic cores in MOSE during endoscopic ultrasound-guided fine-needle aspiration/biopsy(EUS-FNA/FNB).AIM To evaluate the performance of MOSE during EUS-FNA/FNB.METHODS This multicentric prospective study was conducted in 16 centers in 3 countries(Egypt,Iraq,and Morocco)and included 1108 patients with pancreatic,biliary,or gastrointestinal pathology who were referred for EUS examination.We prospectively analyzed the MOSE in 1008 patients with available histopathological reports according to 2 classifications to determine the adequacy of the histological core samples.Data management and analysis were performed using a Statistical Package for Social Sciences(SPSS)version 27.RESULTS A total of 1074 solid lesions were biopsied in 1008 patients with available cytopathological reports.Mean age was 59 years,and 509 patients(50.5%)were male.The mean lesion size was 38 mm.The most frequently utilized needles were FNB-Franseen(74.5%)and 22 G(93.4%),with a median of 2 passes.According to 2 classifications,618 non-bloody cores(61.3%)and 964 good samples(95.6%)were adequate for histological evaluation.The overall diagnostic yield of cytopathology was 95.5%.The cytological examination confirmed the diagnosis of malignancy in 861 patients(85.4%),while 45 samples(4.5%)were inconclusive.Post-procedural adverse events occurred in 33 patients(3.3%).Statistical analysis showed a difference between needle types(P=0.035)with a high sensitivity of FNB(97%).The analysis of the relationship between the MOSE-score and the final diagnosis showed a significant difference between the different scores of the MOSE(P<0.001).CONCLUSION MOSE is a 展开更多
关键词 Macroscopic on-site evaluation Fine-needle aspiration Fine-needle biopsy Endoscopic ultrasound SPECIMEN
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Hepatocellular injury and the mortality risk among patients with COVID-19: A retrospective cohort study 被引量:3
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作者 Ali Madian Ahmed Eliwa +1 位作者 Hytham Abdalla Haitham A Azeem Aly 《World Journal of Hepatology》 2021年第8期939-948,共10页
BACKGROUND Clearly,infection with severe acute respiratory syndrome coronavirus 2 is not limited to the lung but also affects other organs.We need predictive models to determine patients’prognoses and to improve heal... BACKGROUND Clearly,infection with severe acute respiratory syndrome coronavirus 2 is not limited to the lung but also affects other organs.We need predictive models to determine patients’prognoses and to improve health care resource allocation during the coronavirus disease 2019(COVID-19)pandemic.While treating COVID-19,we observed differential outcome prediction weights for markers of hepatocellular injury among hospitalized patients.AIM To investigate the association between hepatocellular injury and all-cause inhospital mortality among patients with COVID-19.METHODS This multicentre study employed a retrospective cohort design.All adult patients admitted to Al-Azhar University Hospital,Assiut,Egypt and Abo Teeg General Hospital,Assiut,Egypt with confirmed COVID-19 from June 1,2020,to July 30,2020 were eligible.We categorized our cohort into three groups of(1)patients with COVID-19 presenting normal aminotransferase levels;(2)patients with COVID-19 presenting one-fold higher aminotransferase levels;and(3)patients with COVID-19 presenting two-fold higher aminotransferase levels.We analysed the association between elevated aminotransferase levels and all-cause in-hospital mortality.The survival analysis was performed using the Kaplan–Meier method and tested by log-rank analysis.RESULTS In total,376 of 419 patients met the inclusion criteria,while 29(8%)patients in our cohort died during the hospital stay.The median age was 40 years(range:28-56 years),and 51%were males(n=194).At admission,54%of the study cohort had liver injury.The pattern of liver injury was hepatocellular injury with an aspartate aminotransferase(AST)predominance.Admission AST levels were independently associated with all-cause in-hospital mortality in the logistic regression analysis.A one-fold increase in serum AST levels among patients with COVID-19 led to an eleven-fold increase in in-hospital mortality(P<0.001).Admission AST levels correlated with C-reactive protein(r=0.2;P<0.003)and serum ferritin(r=0.2;P<0.0002)levels.Admission alanin 展开更多
关键词 COVID-19 Liver injury Aspartate amino transferase All-cause in-hospital mortality Serum ferritin SARS-CoV-2
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