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    题名 作者 年代 出处 被引量
1Numerical and experimental direct shear tests for coarse-grained soils显示文摘The presence of particles larger than the permissible dimensions of conventional laboratory specimens causes difficulty in the determination of shear strength of coarse-grained soils. In this research, the influence of particle size on shear strength of coarse-grained soils was investigated by resorting to experimental tests in different scale and numerical simulations based on discrete element method (DEM). Experimental tests on such soil specimens were based on using the techniques designated as 'parallel' and 'scalping' to prepare gradation of samples in view of the limitation of laboratory specimen size. As a second approach, the direct shear test was numerically simulated on assemblies of elliptical particles. The behaviors of samples under experimental and numerical tests are presented and compared, indicating that the modification of sample gradation has a significant influence on the mechanical properties of coarse-grained soils. It is noted that the shear strengths of samples produced by the scalping method are higher than samples by the parallel method. The scalping method for preparing specimens for direct shear test is therefore recommended. The micromechanical behavior of assemblies under direct shear test is also discussed and the effects of stress level on sample behavior are investigated.Ahad Bagherzadeh-Khalkhali Ali Asghar Mirghasemi 2009Particuology2009,7,1:42
2中国铀矿采冶回顾与展望显示文摘中国铀矿包括火山岩型、花岗岩型、碳硅泥岩型、砂岩型和煤岩型等多种类型。铀矿采冶始于20世纪50年代,早期以火山岩型和煤岩型铀矿常规地下开采为主,部分埋藏较浅的矿床则以露天开采的方式进行;铀的提取采用破磨搅拌浸出或堆浸工艺。20世纪90年代以来逐步向砂岩铀矿开采转型,以采冶一体的原地浸出方式进行开采和铀的提取,按浸出剂的不同主要分为酸法、碱法、中性(CO_(2)+O_(2))等工艺,其中酸法和中性浸出工艺在中国应用最为广泛。近年来微生物浸出技术在铀矿堆浸和地浸方面均有所突破,部分实现工业应用。清洁、高效和数字赋能是铀矿采冶发展的主要趋势,建设绿色、高效、智能的铀矿大基地也正在成为中国天然铀产业高质量发展的新动能。孙占学 Fiaz Asghar 赵凯 周义朋 黎广荣 徐玲玲 2021有色金属(冶炼部分)2021,,8:22
3阔叶猕猴桃叶片离体器官发生和植株再生(英文)显示文摘以阔叶猕猴桃(A ctinidia latifolia M err.)叶片为外植体,通过器官发生途径诱导形成不定芽,探讨了不同激素组合、暗培养时间以及不同浓度的蔗糖对叶片器官发生和植株再生的影响。结果表明,BW +0.1μm ol/L N AA +5μm ol/L Zeatin 附加20g/L 蔗糖,先进行21d 暗培养然后转到光下培养效果最好,6周后不定芽再生频率达91.67%,平均每个外植体再生芽数6.87个。再生芽生根良好,生根率可达100%。首次报道了阔叶猕猴桃的器官发生和植株再生,建立了叶片的高效再生体系,为今后的遗传转化研究奠定了基础。毕静华 刘永立 Syed Asghar 2005果树学报2005,22,4:20
4Crop photosynthetic response to light quality and light intensity显示文摘Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.Iram SHAFIQ Sajad HUSSAIN Muhammad Ali RAZA Nasir IQBAL Muhammad Ahsan ASGHAR Ali RAZA FAN Yuan-fang Maryam MUMTAZ Muhammad SHOAIB Muhammad ANSAR Abdul MANAF YANG Wen-yu YANG Feng 2021Journal of Integrative Agriculture2021,20,1:16
5Indoleamine 2,3-dioxygenase: As a potential prognostic marker and immunotherapeutic target for hepatocellular carcinoma显示文摘Tumor cells induce an immunosuppressive microen-vironment which leads towards tumor immune escape. Understanding the intricacy of immunomodulation by tumor cells is essential for immunotherapy. Indoleamine 2,3-dioxygenase(IDO) is an immunosuppressive enzyme which mediates tumor immune escape in various cancers including hepatocellular carcinoma(HCC). IDO up-regulation in HCC may lead to recruitment of regulatory T-cells into tumor microenvironment and therefore inhibit local immune responses and promote metastasis. HCC associated fibroblasts stimulate natural killer cells dysfunction through prostaglandin E2 and subsequently IDO promotes favorable condition for tumor metastasis. IDO up-regulation induces immuno-suppression and may enhance the risk of hepatitis C virus and hepatitis B virus induced HCC. Therefore, IDO inhibitors as adjuvant therapeutic agents may have clinical implications in HCC. This review proposes future prospects of IDO not only as a therapeutic target but also as a prognostic marker for HCC.Kashif Asghar Asim Farooq Bilal Zulfiqar Muhammad Usman Rashid 2017World Journal of Gastroenterology2017,23,13:16
6Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler Irrigation显示文摘Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran(a 0.17 ha peach orchard and a 0.24 ha orange orchard) to protect peach blossoms and orange trees leaves and fruits from low temperature damage.The experiment used a system that monitored the trees and air temperatures using two thermistors.The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO.In the peach orchard,the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004.The system successfully kept peach flowers above the critical temperature,i.e.,-4.0°C in spring 2004(control block -4.12°C,and sprinkled block +0.5°C) during all events.Similar results were obtained in the orange orchard during three frost events in the winter of 2004,during which the tree temperatures were at least 2.5°C above the critical temperature.Results from field tests show that the system can effectively protect the peach blossoms from damage.Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill.Calculations indicated that when using variable application rates,the amount of water used can be reduced by 54.3%.Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom,Iran.Results showed a significant temperature control in the experimental block,especially in the central part of the orchard,but the block margins(about 3.6% of the total area) were at the risk of low temperature due to the wind drift effects.Ali Asghar Ghaemi Mohammad Rafie Rafiee Ali Reza Sepaskhah 2009Agricultural Sciences in China2009,8,1:14
7Identification of squamous cell carcinoma associated proteins by proteomics and loss of beta tropomyosin expression in esophageal cancer显示文摘AIM: To assess the proteome of normal versus tumor tissue in squamous cell carcinoma of the esophagus (SCCE) in Iranian patients and compare our results with former reports by using proteomics. METHODS: Protein was extracted from normal and tumor tissues. Two dimensional electrophoresis was carried out and spots with differential expression were identified with mass spectrometry. RNA extraction and RT-PCR along with immunodetection were performed. RESULTS: Fourteen proteins were found whose expression levels differed in tumor compared to normal tissues. Mass spectrometric analysis resulted in the identification of β-tropomyosin (TMβ), myosin light chain 2 (and its isoform), myosin regulatory light chain 2, peroxyredoxin 2, annexinⅠand an unknown polypeptide as the down regulated polypeptides in tumor tissue. Heat shock protein 70 (HSP70), TPM4-ALK fusion oncoprotein 2, myosin light polypeptide 6, keratinⅠ, GH16431p and calreticulin were the up-regulated polypeptides found in tumor tissue. Several of these proteins, such as TMβ,HSP70, annexinⅠ, calreticulin, TPM4-ALK and isoforms of myosins, have been well recognized in tumorigenesis of esophageal or other types of cancers. CONCLUSION: Our study not only supports the involve- ment of some of the formerly reported proteins in SCCE but also introduces additional proteins found to be lost in SCCE, including TMβ.Ferdous Rastgar Jazii Zahra Najafi Reza Malekzadeh Thomas P Conrads Abed Ali Ziaee Christian Abnet Mansour Yazdznbod Ali Asghar Karkhane Ghasem H Salekdeh 2006World Journal of Gastroenterology2006,12,44:14
8Investigating the first-order flotation kinetics models for Sarcheshmeh copper sulfide ore显示文摘This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stage,influence of pH,solid concentration,water chemistry and the amount of collector dosage were investigated on kinetics parameters including flotation rate constant and ultimate recovery.The results indicated that that perfectly mixed reactor model and Kelsall model gave the best and the weakest fit to the experimental data,respectively.It was observed that flotation rate constant and ultimate recovery were strongly affected by chemical factors investigated especially water quality.The flotation rate constant decreased with increasing the solids content,while ultimate recovery increased to certain value and thereafter reduced.It was also found that the most values of flotation rate constant and ultimate recovery obtained in dosage of collector are 30 and 40 g/t,respectively.Asghar Azizi Ahmad Hassanzadeh Behnam Fadaei 2015International Journal of Mining Science and Technology2015,25,5:12
9Computational fluid dynamics(CFD) simulation of effect of baffles on separation in mixer settler显示文摘The main ideas in the development of the solvent extraction mixer settler focused on achieving clean phase separation,minimizing the loss of the reagents and decreasing the surface area of the settlers.The role of baffles in a mechanically agitated vessel is to ensure even distribution,reduce settler turbulence,promote the stability of power drawn by the impeller and to prevent swirling and vortexing of liquid,thus,greatly improving the mixing of liquid.The insertion of the appropriate number of baffles clearly improves the extent of liquid mixing.However,excessive baffling would interrupt liquid mixing and lengthen the mixing time.Computational fluid dynamics(CFD) provides a tool for determining detailed information on fluid flow(hydrodynamics) which is necessary for modeling subprocesses in mixer settler.A total of 54 final CFD runs were carried out representing different combinations of variables like number of baffles,density and impeller speed.CFD data shows that amount of separation increases with increasing baffles number and decreasing impeller speed.Mohsen Ostad Shabani Ali Mazahery Mehdi Alizadeh Ali Asghar Tofigh Mohammad Reza Rahimipour Mansour Razavi Alireza Kolahi 2012International Journal of Mining Science and Technology2012,22,5:12
10Critical role of SDF-1/CXCR4 signaling pathway in stem cell homing in the deafened rat cochlea after acoustic trauma显示文摘Previous animal studies have shown that stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor-4(CXCR4) signaling pathway plays an important role in the targeted migration of bone marrow-derived mesenchymal stem cells(BMSCs) to the injured area. In the present study, we aimed to investigate the potential role of chemotactic SDF-1/CXCR4 signaling pathway in the homing of transplanted BMSCs to the injured cochlea after noise-induced hearing loss(NIHL) in a rat model. White noise exposure(110 d B) paradigm was used for hearing loss induction in male rats for 6 hours in 5 days. Distortion-product otoacoustic emission(DPOAE) responses were recorded before the experiment and post noise exposure. Hoechst 33342-labeled BMSCs and CXCR4 antagonist(AMD3100)-treated BMSCs were injected into the rat cochlea through the round window. SDF-1 protein expression in the cochlear tissue was assayed using western blot assay. The number of labeled BMSCs reaching the endolymph was determined after 24 hours. SDF-1 was significantly increased in the cochlear tissue of rats in the noise exposure group than in the control group. The number of Hoechst 33342-labeled BMSCs reaching the endolymph of the cochlea was significantly smaller in the AMD3100-treated BMSCs group than in the normal BMSCs group. Our present findings suggest that the SDF-1/CXCR4 signaling pathway has a critical role in BMSCs migration to the injured cochlea in a rat model of noise-induced hearing loss.Ali Asghar Peyvandi Navid Ahmady Roozbahany Hassan Peyvandi Hojjat-Allah Abbaszadeh Niloofar Majdinasab Mohammad Faridan Somayeh Niknazar 2018Neural Regeneration Research2018,13,1:11
11超级电容器用生物质基多孔炭的研究进展显示文摘在最近的几十年中,超级电容器(SC)已在电化学能量存储设备中获得了更为重要的地位。SC为使用寿命长的能量存储设备提供了可观的功率密度和令人满意的能量密度,适用于多种应用。因此,这些装置的进一步发展依赖于提供合适,低成本,环境友好和丰富的材料作为SC的电极活性材料。在用于SC的电极材料中,活性炭表现出优异的性能。它们具有优异的电化学效率,高比表面积,高吸附性,可调节的表面化学性质,快速的离子/电子传输,低成本和丰富的特性,使其成为SC电极的最佳材料。如果从生物质前驱体制备活性炭,则可以协同增强这些优势。由于生物质为可再生来源,低成本,便捷的加工过程以及对环境的友好性,研究者们将注意力集中在生物质上。在本文中,试图全面了解作为电化学储能装置的SC的基本原理。然后,对各种来源的生物质进行分类和分析。最后,讨论了这些生物质前驱体作为SCs电极材料的应用和活化技术。Majid Shaker Ali Asghar Sadeghi Ghazvini 曹蔚琦 Reza Riahifar 葛奇 2021新型炭材料2021,36,3:9
12Particle shape consideration in numerical simulation of assemblies of irregularly shaped particles显示文摘The mechanical behavior of granular materials depends much on the shape of the constituent particles. Therefore appropriate modeling of particle, or grain, shape is quite important. This study employed the method of direct modeling of grain shape (Matsushima & Saomto, 2002), in which, the real shape of a grain is modeled by combining arbitrary number of overlapping circular elements which are connected to each other in a rigid way. Then, accordingly, a discrete-element program is used to simulate the assembly of grains. In order to measure the effects of grain shape on mechanical properties of assembly of grains, three types of grains-high angular grains, medium angular grains and round grains are considered where several biaxial tests are conducted on assemblies with different grain types. The results show that the angularity of grains greatly affects the behavior of granular soil.Saba Abedi Ali Asghar Mirghasemi 2011Particuology2011,9,4:8
13Micromechanics of breakage in sharp-edge particles using combined DEM and FEM显示文摘By combining DEM(Discrete Element Method)and FEM(Finite Element Method),a model is established to simulate the breakage of two-dimensional sharp-edge particles,in which the simulated particles are assumed to have no cracks.Particles can,however,crush during different stages of the numerical analysis,if stress-based breakage criteria are fulfilled inside the particles.With this model,it is possible to study the influence of particle breakage on macro-and micro-mechanical behavior of simulated angular materials.Two series of tests,with and without breakable particles,are simulated under different confining pressures based on conditions of biaxial tests.The results,presented in terms of micromechanical behavior for different confining pressures,are compared with macroparameters.The influence of particle breakage on microstructure of sharp-edge materials is discussed and the related confining pressure effects are investigated.Breakage of particles in rockfill materials are shown to reduce the anisotropy coefficients of the samples and therefore their strength and dilation behaviors.Ahad Bagherzadeh-Khalkhali Ali Asghar Mirghasemi Soheil Mohammadi 2008Particuology2008,6,5:8
14Synthesis and Characterization of Nano-hydroxyapatite Powder Using Wet Chemical Precipitation Reaction显示文摘Hydroxyapatite(HA) nano-powder was synthesized via wet chemical technique in a used precipitation reaction,in which Ca(OH)_2 and H_3PO_4 were used as precursors.Deionised water was used as a diluting media for the reaction and ammonia was used to adjust the pH.The synthetic HA nano-powder has some medical applications such as a coating material in orthopaedic implants and in dental.HA powder has been studied at different temperatures from 100 to 800 ℃ to achieve the stoichiometric Ca/P ratio 1.667.The optimum temperature was found to be 600 ℃.Above this temperature,the HA powder decomposed to CaO.The crystallite size of HA powder was found to be in the range of 8.47—24.47 nm.The crystallographic properties were evaluated by X-ray diffraction,Fourier transform infrared spectroscopy,energy dispersive Xray spectroscopy and scanning electron microscopy.The results show that,high purity of nano-hydroxyapatite powders could be obtained at low temperatures,and the crystallinity,crystallite size and Ca/P ratio of the resulting nanoparticles were found to be dependent on the calcination temperature.When Ca/P ratio exceeded1.75,formation of CaO phase was observed.Syed Sibte Asghar Abidi Qasim Murtaza 2014Journal of Materials Science & Technology2014,30,4:8
15Oxidative Desulfurization of Non-hydrotreated Kerosene Using Hydrogen Peroxide and Acetic Acid显示文摘The oxidative desulfurization of a real refinery feedstock (i.e.,non-hydrotreated kerosene with total sulfur mass content of 0.16%) with a mixture of hydrogen peroxide and acetic acid was studied.The influences of various operating parameters including reaction temperature (T),acid to sulfur molar ratio (nacid/nS),and oxidant to sulfur molar ratio (nO/nS) on the sulfur removal of kerosene were investigated.The results revealed that an increase in the reaction temperature (T) and nacid/nS enhances the sulfur removal.Moreover,there is an optimum nO/nS related to the reaction temperature and the best sulfur removal could be obtained at nO/nS=8 and 23 for the reaction temperatures of 25 and 60°C,respectively.The maximum observed sulfur removal in the present oxidative desulfurization system was 83.3%.Asghar Molaei Dehkordi Mohammad Amin Sobati Mohammad Ali Nazem 2009Chinese Journal of Chemical Engineering2009,17,5:8
16新疆蒙其古尔矿床铀矿石CO_(2)+O_(2)中性浸出试验显示文摘采用新疆某砂岩铀矿石为原料,在实验室开展了分别以矿床地下水和地浸尾液配制浸出剂的CO_(2)+O_(2)中性浸出试验,研究不同铀矿石的铀浸出差异,以及对地浸具有影响的Fe、S的氧化与碳酸盐的溶解沉淀状况。结果表明,地下水和地浸尾液配制的浸出剂对相同矿石的浸出结果没有明显差异,矿石铀含量是最主要影响因素,浸出铀浓度与矿石铀含量显著正相关;静态浸出过程中,铀在体系中的扩散不充分,底部铀浓度显著高于上部,通常静态浸泡比搅拌浸出的铀浸出率低与此有一定关系;Fe的氧化较显著,浸后矿石FeO含量下降37%~62%,S也有所氧化;碳酸盐处于接近饱或超饱和状态,应将体系pH控制在6.5以内,以避免方解石和白云石发生饱和沉淀。Fiaz Asghar 周义朋 孙占学 黎广荣 徐玲玲 赵凯 2021有色金属(冶炼部分)2021,,8:8
17Rare Earth Elements Geochemistry of Sheikh-Marut Laterite Deposit,NW Mahabad,West-Azarbaidjan Province,Iran显示文摘在 Sheikh-Marut 的红土沉积物(NW Mahabad, West-Azarbaidjan 省,伊朗) 发生在 middleupper 以内二叠的碳酸盐岩石。它由在长度扩大超过 4.2 km 并且有厚度从 3 ~ 14 m 的七层状或不连续的透镜的层组成。矿石包含的矿物学的数据表演 kaolinite 和同样主要的赤铁矿和 boehmite,水铝石, halloysite, amesite,锐钛矿,和象次要的矿物质的 muscovite-illite 分阶段执行。在矿石的计算 Ce 异例价值从 0.05 ~ 20.84 。保守索引(例如, Eu/Eu *) 建议这沉积物是改变的一个产品并且玄武岩的岩石捱过。有来临到碳酸盐基岩的矿石的 REE 值的有韵律的增长出现一在原处, lateritization 的出现处理。元素的集体变化计算显示也就是沥滤的二竞争过程和固定是在获得的结果显示出的这沉积物在 REE ( LaLu )的集中变化调整因素的专业由碳酸盐基岩捱过答案的那 pH 增加,有机物的存在,并且有器官的 ligands 的 comlexation 的度在 lateritization 期间在 REE 的分发起了显著作用。进一步的 geochemical 考虑表明第二等的磷酸盐, Mn 氧化物和 -hydroxides, 水铝石,和锐钛矿是为在这沉积物的 REE 的潜在的主人。Ali ABEDINI Ali Asghar CALAGARI 2013Acta Geologica Sinica(English Edition)2013,87,1:7
18Advances in healthcare wearable devices显示文摘Wearable devices have found numerous applications in healthcare ranging from physiological diseases,such as cardiovascular diseases,hypertension and muscle disorders to neurocognitive disorders,such as Parkinson’s disease,Alzheimer’s disease and other psychological diseases.Different types of wearables are used for this purpose,for example,skin-based wearables including tattoobased wearables,textile-based wearables,and biofluidic-based wearables.Recently,wearables have also shown encouraging improvements as a drug delivery system;therefore,enhancing its utility towards personalized healthcare.These wearables contain inherent challenges,which need to be addressed before their commercialization as a fully personalized healthcare system.This paper reviews different types of wearable devices currently being used in the healthcare field.It also highlights their efficacy in monitoring different diseases and applications of healthcare wearable devices(HWDs)for diagnostic and treatment purposes.Additionally,current challenges and limitations of these wearables in the field of healthcare along with their future perspectives are also reviewed.Sheikh M.A.Iqbal Imadeldin Mahgoub E Du Mary Ann Leavitt Waseem Asghar 2021npj Flexible Electronics2021,5,1:6
19Mixed-effects modeling for tree height prediction models of Oriental beech in the Hyrcanian forests显示文摘Height–diameter relationships are essential elements of forest assessment and modeling efforts.In this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech(Fagus orientalis Lipsky) in the Hyrcanian Forest in Iran.The predictive performance of these models was first assessed by different evaluation criteria: adjusted R^2(R^2_(adj)),root mean square error(RMSE),relative RMSE(%RMSE),bias,and relative bias(%bias) criteria.The best model was selected for use as the base mixed-effects model.Random parameters for test plots were estimated with different tree selection options.Results show that the Chapman–Richards model had better predictive ability in terms of adj R^2(0.81),RMSE(3.7 m),%RMSE(12.9),bias(0.8),%Bias(2.79) than the other models.Furthermore,the calibration response,based on a selection of four trees from the sample plots,resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results.Siavash Kalbi Asghar Fallah Pete Bettinger Shaban Shataee Rassoul Yousefpour 2018Journal of Forestry Research2018,29,5:6
20Effects of partial slip on flow of a third grade fluid显示文摘这篇论文是经过一个多孔的盘子与的第三等级液体的旋转流动的分析研究部分滑动效果。它为聚合物的学习担任一个流动模型。分析答案用 homotopy 分析方法(火腿) 被决定了。S. Asghar M. Mudassar Gulzar M. Ayub 2006Acta Mechanica Sinica2006,22,5:6
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