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137篇 您的检索式:作者名="Muhammad Irfan"
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1The role of chemosensory protein 10 in the detection of behaviorally active compounds in brown planthopper, Nilaparvata lugens显示文摘Chemosensory proteins(CSPs)play important roles in insects’chemoreception,although their specific functional roles have not been fully elucidated.In this study,we conducted the developmental expression patterns and competitive binding assay as well as knock‐down assay by RNA interference both in vitro and in vivo to reveal the function of NlugCSP10 from the brown planthopper(BPH),Nilaparvata lugens(Stål),a major pest in rice plants.The results showed that NlugCSP10 messenger RNA was significantly higher in males than in females and correlated to gender,development and wing forms.The fluorescence binding assays revealed that NlugCSP10 exhibited the highest binding affinity with cis‐3‐hexenyl acetate,eicosane,and(+)‐β‐pinene.Behavioral assay revealed that eicosane displayed attractant activity,while cis‐3‐hexenyl acetate,similar to(+)‐β‐pinene significantly repelled N.lugens adults.Silencing of NlugCSP10,which is responsible for cis‐3‐hexenyl acetate binding,significantly disrupted cis‐3‐hexenyl acetate communication.Overall,findings of the present study showed that NlugCSP10 could selectively interrelate with numerous volatiles emitted from host plants and these ligands could be designated to develop slow‐release mediators that attract/repel N.lugens and subsequently improve the exploration of plans to control this insect pest.Muhammad Irfan Waris Aneela Younas Muhammad Muzammal Adeel Shuang-Gang Duan Sundas Rana Quershi Rana Muhammad Kaleem Ullah Man-Qun Wang 2020Insect Science2020,27,3:9
2A review on promising phytochemical, nutritional and glycemic control studies on Moringa oleifera Lam. in tropical and sub-tropical regions显示文摘Plants have provided sources to find novel compounds. These plants are being used as therapeutic purposes since the birth of mankind. The traditional healers normally utilize medicinal plants as crude drugs while scientists using the folk claim as guides to explore medicinal plants. Moringa oleifera is a famous edible plant having therapeutic and nutritive values. The present study was designed to cumulate the research data regarding to what extent, phytochemical, nutritional and glycemic control studies has been explored using its different extracts. The articles indicated that the powder, aqueous, methanol and ethanol extracts of Moringa oleifera(leaves, pods, seeds, stem and root bark) have significant therapeutic herbal potential to treat diabetes mellitus. Collectively, the mechanism behind is intestinal glucose inhibition, insulin release as well as decrease in insulin resistance probably regeneration of b-cells of pancreas, increase in glutathione and reduction in malondialdehyde. Conclusively, this article give descriptive information about antidiabetic effect, claimed marker compounds and proposed antihyperglycemic mechanism of a single plant. It can be suggested a potential herbal source to treat diabetes mellitus as being widely accepted by major population as nutrition and therapeutic agent.Hafiz Irfan Muhammad Mohd Zaini Asmawi Nurzalina Abdul Karim Khan 2016Asian Pacific Journal of Tropical Biomedicine2016,6,10:8
3柞蚕蛹解除滞育过程中海藻糖合成酶基因的表达变化显示文摘【目的】克隆柞蚕Antheraea pernyi海藻糖合成酶(trehalose-6-phosphate synthase,TPS)基因,并对其进行组织表达分析,探讨该基因在柞蚕滞育蛹解除滞育过程中的表达规律,为阐明柞蚕滞育期间碳水化合物代谢规律与蛹滞育解除的关系提供数据支持。【方法】利用PCR及3'RACE技术从柞蚕幼虫脂肪体组织中克隆得到TPS基因,并进行生物信息学分析;RT-PCR检测该基因在柞蚕幼虫各组织中的表达分布,进一步采用Real-time PCR分析柞蚕滞育蛹解除滞育过程中该基因在脂肪体组织和血淋巴中的表达量变化。【结果】克隆获得柞蚕海藻糖合成酶基因并命名为ApTPS。其开放阅读框长2 487 bp,编码828个氨基酸,蛋白预测分子量为93.19 k D,等电点(p I)4.61;无信号肽,无跨膜区。蛋白质亚细胞定位预测该蛋白定位于细胞质中;蛋白质结构域分析表明,ApTPS有两个保守功能区:TPS(第22-497位氨基酸)和TPP(第532-772位氨基酸)。组织特异性分析表明,ApTPS基因在柞蚕幼虫脂肪体中表达量最高;柞蚕解除滞育过程中,ApTPS在脂肪体和血淋巴中的表达量均有所升高,且显著高于对照组(P<0.05),但血淋巴中表达量的升高滞后于脂肪体。【结论】结果提示ApTPS参与了柞蚕蛹滞育中碳水化合物代谢调控并在其中发挥重要作用,与柞蚕蛹滞育解除关系密切。黄伶 孙良振 王勇 汝玉涛 Muhammad IRFAN 姜义仁 石生林 杨瑞生 李喜升 秦利 2016昆虫学报2016,59,9:7
4Schizonepeta tenuifolia inhibits collagen stimulated platelet function via suppressing MAPK and Akt signaling显示文摘The prevalence of cardiovascular diseases(CVDs)is increasing at a rapid pace in developed countries,and CVDs are the leading cause of morbidity and mortality.Natural products and ethnomedicine have been shown to reduce the risk of CVDs.Schizonepeta(S.)tenuifolia is a medicinal plant widely used in China,Korea,and Japan and is known to exhibit anti-inflammatory,antioxidant,and immunomodulatory activities.We hypothesized that given herbal plant exhibit pharmacological activities against CVDs,we specifically explored its effects on platelet function.Platelet aggregation was evaluated using standard light transmission aggregometry.Intracellular calcium mobilization was assessed using Fura-2/AM,and granule secretion(ATP release)was measured in a luminometer.Fibrinogen binding to integrin a_(Ⅱb)β_3,was assessed using flow cytometry.Phosphorylation of mitogen-activated protein kinase(MAPK)signaling molecules and activation of the protein kinase B(Akt)was assessed using Western blot assays.S.tenuifolia,extract potently and significantly inhibited platelet aggregation,calcium mobilization,granule secretion,and fibrinogen binding to integrin a_(Ⅱb)β_3.Moreover,all extracts significantly inhibited MAPK and Akt phosphorylation.S.tenuifolia extract inhibited platelet aggregation and granule secretion,and attenuated collagen mediated GPVI downstream signaling,indicating the potential therapeutic effects of these plant extracts on the cardiovascular system and platelet function.We suggest that S.tenuifolia extract may be a potent candidate to treat platelet-related CVDs and to be used as an antiplatelet and antithrombotic agent.Bo-Ra Jeon Muhammad Irfan Minki Kim Seung Eun Lee Jeong Hoon Lee Man Hee Rhee 2019The Journal of Biomedical Research2019,33,4:6
5Predictors of response to antiviral therapy in patients with chronic hepatitis C from Pakistani population显示文摘背景丙肝病毒(HCV ) 在全世界组成一个主要公共健康问题,特别在开发象巴基斯坦一样的国家。在这研究,我们估计了在长期的丙肝病人的治疗在这研究由性,年龄,和病毒的 load.Methods 分类的干扰素(INF ) 的结果,有遗传型 3 的 750 个 HCV 积极病人被选择,从哪个 616 完成了全部治疗。他们的个人历史,支持处理的 HCV RNA 和浆液丙氨酸 transaminase (中高音) 是 quantified.Patients 与 INF- 2b 的联合治疗被对待 300 万个单位(三次一个星期) 正 ribavirin (1000-1200mg 每天) 为 24 个星期。在 24 个星期以后,他们的 HCV RNA 和浆液中高音水平是从 616 个病人,的 quantified.Results (63.5%) 391 对治疗学的政体(加 ribavirin 的 INF- 2b ) 作出回应。在应答者之中, 27.1% 是男人, 36.4% 是女人。最好的治疗反应在有 Iow 的病人被观察病毒的负担 8 ?????牴湡睳汥 吗??Hafsa Aziz Muhammad Amin Athar Shahnaz Murtaza Javaid Irfan Yasir Waheed Iram Bilal Abida Raza 2011Chinese Medical Journal2011,,9:6
6Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying显示文摘Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying(DSR-AWD) in comparison with direct seeded rice at field capacity(DSRFC). Seed priming treatments were osmo-priming with KCl(2.2%), Ca Cl2(2.2%) and moringa leaf extracts(MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with Ca Cl2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with Ca Cl2 in DSRAWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or Ca Cl2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or Ca Cl2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.Hafeez Ur REHMAN Muhammad KAMRAN Shahzad Maqsood Ahmed BASRA Irfan AFZAL Muhammad FAROOQ 2015Rice science2015,22,4:5
7Highly efficient and selective photocatalytic dehydrogenation of benzyl alcohol for simultaneous hydrogen and benzaldehyde production over Ni-decorated Zn_(0.5)Cd_(0.5)S solid solution显示文摘Photocatalytic conversion of solar energy into hydrogen and high value-added fine chemicals has attracted increasing attention. Herein, we demonstrate an efficient photocatalytic system for simultaneous hydrogen evolution and benzaldehyde production by dehydrogenation of benzyl alcohol over Nidecorated Zn_(0.5)Cd_(0.5)S solid solution under visible light. The photocatalytic system shows an excellent hydrogen production rate of 666.3 μmol h^(-1) with high stability. The optimal apparent quantum yield of52.5% is obtained at 420 nm. This noble-metal-free photocatalytic system displays much higher activity than pure Zn_(0.5)Cd_(0.5)S and Pt-loaded Zn_(0.5)Cd_(0.5)S solid solution. Further studies reveal that the metallic Ni nanocrystals play an important role in accelerating the separation of photogenerated charge carriers and the subsequent cleavage of α-C–H bond during dehydrogenation of benzyl alcohol.Lei Zhang Daochuan Jiang Rana Muhammad Irfan Shan Tang Xin Chen Pingwu Du 2019Journal of Energy Chemistry2019,28,3:5
8Isolation and characterization of xanthine oxidase inhibitory constituents of Pyrenacantha staudtii显示文摘Six compounds have been isolated from the leaves of Pyrenacantha staudtii, two of which are new compounds. The new compounds have been characterized as kaempherol 3-O-β-rhamnopyranosyl (1→6)-β-D-glucopyranoside (1) and 4-β-glucopyranosyl-(2-furyl)-5-methy-l,2-glucopyranoside phenylmethanone (2). The known compounds are 3-pyridinecarboxylic acid (3), β-sitosterol (4), sitosterol 3-O-β-glucopyranoside (5) and taraxerol (6). Their structures were determined by spectroscopic and chemical evidences. The two new compounds together with 3-pyridinecarboxylic acid showed significant in vitro xanthine oxidase inhibitory activity. To the best of our knowledge, this is the first report of these compounds from this plant.Abiodun FALODUN Muhammad Irfan QADIR Muhammad Iqbal CHOULDARY 2009药学学报2009,44,4:4
9Overexpression of the phytochrome B gene from Arabidopsis thaliana increases plant growth and yield of cotton (Gossypium hirsutum)显示文摘The phytochrome B (PHYB) gene of Arabidopsis thaliana was introduced into cotton through Agrobacterium tumefaciens.Integration and expression of PHYB gene in cotton plants were confirmed by molecular evidence.Messenger RNA (mRNA) expression in one of the transgenic lines,QCC11,was much higher than those of control and other transgenic lines.Transgenic cotton plants showed more than a two-fold increase in photosynthetic rate and more than a four-fold increase in transpiration rate and stomatal conductance.The increase in photosynthetic rate led to a 46% increase in relative growth rate and an 18% increase in net assimilation rate.Data recorded up to two generations,both in the greenhouse and in the field,revealed that overexpression of Arabidopsis thaliana PHYB gene in transgenic cotton plants resulted in an increase in the production of cotton by improving the cotton plant growth,with 35% more yield.Moreover,the presence of the Arabidopsis thaliana PHYB gene caused pleiotropic effects like semi-dwarfism,decrease in apical dominance,and increase in boll size.Abdul Qayyum RAO Muhammad IRFAN Zafar SALEEM Idrees Ahmad NASIR Sheikh RIAZUDDIN Tayyab HUSNAIN 2011Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2011,12,4:4
10非金属光敏剂石墨烯量子点与磷化镍耦合用于可见光光催化制氢(英文)显示文摘利用光催化反应制取氢气是满足未来能源可持续利用的一个很有效的方法.然而,如何去开发和利用高效且稳定的非金属光催化剂用于产氢反应是目前所面临的一个巨大的挑战.最近,非金属纳米碳基材料由于其诸多优点而吸引了人们广泛的关注,比如价格低廉、环境友好和良好的稳定性等.另外,石墨烯量子点由于具有很好的水溶性、低毒性,良好的生物兼容性和很好的光学稳定性等优点而被当作是一种能够替代传统量子点的很有前途的材料.除此之外,石墨烯量子点的带隙还可以通过控制其颗粒大小和其表面所带的官能团来进行灵活调控.另一方面,金属磷化物(磷化镍、磷化钴等)已经被证实了是很好的水分解制氢的非贵金属助催化剂,它们可以加快光生电子和空穴的分离,从而提高光催化活性.本文利用非金属光敏剂石墨烯量子点与非贵金属助催化磷化镍进行耦合制备复合光催化剂,实现了在可见光照射下进行光催化制氢.在最优条件下,复合光催化剂的产氢速率为空白石墨烯量子点的94倍,甚至与在空白量子点上负载1.0wt%Pt的产氢速率相当.产氢速率的大幅度提升可能是由于在石墨烯的量子点和磷化镍之间形成了半导体–金属接触界面,从而更有效地促进了光生载流子的传输过程.石墨烯量子点本身有着很好的水溶性,从而利用机械搅拌的方法与磷化镍进行耦合,并在可见光下进行产氢反应.本文采用红外光谱(FTIR)、透射电镜(TEM)、紫外可见光谱(UV-Vis)和荧光光谱(PL)等表征手段研究了空白量子点表面所带的官能团、尺寸大小和光学性能.采用TEM和PL等表征手段来研究复合光催化剂的形貌和产氢性能提高的原因.对于空白量子点,FTIR结果表明,其表面带有–OH等官能团;TEM结果表明,它的尺寸大小大概在3.6±0.5 nm;UV-Vis结果表明,其在可见光区域有着很强的光吸收;PL结果表明,其在波长约为540 nm处有着很强的吸收峰,所对应的带隙约为2.3 eV.对于复合光催化剂,TEM测试结果表明石墨烯量子点在磷化镍上随机分布;从PL结果可见,复合光催化剂的荧光强度明显降低,说明了光生电子从量子点到磷化镍的有效转移。祝亮 岳秋地 江道传 陈涣淋 Rana Muhammad Irfan 杜平武 2018Chinese Journal of Catalysis2018,39,11:4
11Seed Priming Influence on Early Crop Growth, Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)显示文摘Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L-1 salicylic acid(SA), 2.2% CaCl2 and 3.3% moringa leaf extract(MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2reduced crop branching and fl owering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index(4.12%) and oil contents(13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play signifi cant role to improve early crop growth and seed yields of linola.Hafeez ur Rehman Muhammad Qaiser Nawaz Shahzad Maqsood Ahmed Basra Irfan Afzal Azra Yasmeen Fayyaz ul-Hassan 2014Journal of Integrative Agriculture2014,13,5:4
12Review:Botnet detection techniques: review, future trends, and issue显示文摘In recent years, the Internet has enabled access to widespread remote services in the distributed computing environment; however, integrity of data transmission in the distributed computing platform is hindered by a number of security issues. For instance, the botnet phenomenon is a prominent threat to Internet security, including the threat of malicious codes. The botnet phenomenon supports a wide range of criminal activities, including distributed denial of service(DDoS) attacks, click fraud, phishing, malware distribution, spam emails, and building machines for illegitimate exchange of information/materials. Therefore, it is imperative to design and develop a robust mechanism for improving the botnet detection, analysis, and removal process. Currently, botnet detection techniques have been reviewed in different ways; however, such studies are limited in scope and lack discussions on the latest botnet detection techniques. This paper presents a comprehensive review of the latest state-of-the-art techniques for botnet detection and figures out the trends of previous and current research. It provides a thematic taxonomy for the classification of botnet detection techniques and highlights the implications and critical aspects by qualitatively analyzing such techniques. Related to our comprehensive review, we highlight future directions for improving the schemes that broadly span the entire botnet detection research field and identify the persistent and prominent research challenges that remain open.Ahmad KARIM Rosli Bin SALLEH Muhammad SHIRAZ Syed Adeel Ali SHAH Irfan AWAN Nor Badrul ANUAR 2014Journal of Zhejiang University-Science C(Computers and Electronics)2014,15,11:4
13Seed priming improves early seedling vigor, growth and productivity of spring maize显示文摘Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water(hydropriming), Ca Cl2(2.2%, osmopriming), moringa leaf extracts(MLE 3.3%, osmopriming) and salicylic acid(SA, 50 mg L–1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in early planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyll contents followed by osmopriming with Ca Cl2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed priming; however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.Hafeez ur Rehman Hassan Iqbal Shahzad M A Basra Irfan Afzal Muhammad Farooq Abdul Wakeel WANG Ning 2015Journal of Integrative Agriculture2015,14,9:3
14Exploring the potential of Sentinel-2A satellite data for aboveground biomass estimation in fragmented Himalayan subtropical pine forest显示文摘The Sentinel-2 A satellite having embedded advantage of red edge spectral bands offers multispectral imageries with improved spatial,spectral and temporal resolutions as compared to the other contemporary satellites providing medium resolution data.Our study was aimed at exploring the potential of Sentinel-2 A imagery to estimate Above Ground Biomass(AGB) of Subtropical Pine Forest in Pakistan administered Kashmir.We developed an AGB predictive model using field inventory and Sentinel 2 A based spectral and textural parameters along with topographic features derived from ALOS Digital Elevation Model(DEM).Field inventory data was collected from 108 randomly distributed plots(0.1 ha each) across the study area.The stepwise linear regression method was employed to investigate the potential relationship between field data and corresponding satellite data.Biomass and carbon mapping of the study area was carried out through established AGB estimation model with R(o.86),R2(0.74),adjusted R2(0.72) and RMSE value of 33 t/ha.Our results showed that first order textures(mean,standard deviation and variance) significantly contributed in AGB predictive modeling while only one spectral band ratio made contribution from spectral domain.Our study leads to the conclusion that Sentinel-2 A optical data is a potential source for AGB estimation in subtropical pine forest of the area of interest with added benefit of its free of cost availability,higher quality data and long-term continuity that can be utilized for biomass carbon distribution mapping in the resource constraint study area for sustainable forest management.Mobushir Riaz KHANI Iftikhar Ahmad KHAN Muhammad Hasan Ali BAIG LIU Zheng-jia Muhammad Irfan ASHRAF 2020Journal of Mountain Science2020,17,12:2
15ERP系统在中国企业实施的关键成功要素显示文摘本文定性研究关键成功因素法(CSF)与ERP系统在中国企业实施的相互联系,该研究主要采用多案例研究方法,数据通过对4个组织进行问卷调查获得。5个命题是基于现有文献中归纳的确定因素提出的,并且这些命题已经在其他案例研究中得到了证实。本研究旨在探讨,以往的学术研究中得到认同的关键成功因素法,在中国企业实施ERP系统的情况下,是否值得慎重考虑。研究结果表明,在实施ERP系统的情况下,培训的质量和数量,高层管理的支持和参与以及供应商的支持,这3个因素十分重要并且是中国企业的实际考核因素。Muhammad Aamir Obaid Khattak 佘元冠 李秋梦 Zahid A. Memon Nausheen Sayed Muhammad Irfan 2013中国管理信息化2013,16,19:2
16Silver Nano Islands Enhanced Raman Scattering on Large Area Grating Substrates Fabricated by Two Beam Laser Interference显示文摘ABID Muhammad Irfan WANG Lei ZHANG Xu-lin XU Ying 2013Chemical Research in Chinese Universities2013,29,5:2
17Week Ahead Electricity Power and Price Forecasting Using Improved DenseNet-121 Method显示文摘In the Smart Grid(SG)residential environment,consumers change their power consumption routine according to the price and incentives announced by the utility,which causes the prices to deviate from the initial pattern.Thereby,electricity demand and price forecasting play a significant role and can help in terms of reliability and sustainability.Due to the massive amount of data,big data analytics for forecasting becomes a hot topic in the SG domain.In this paper,the changing and non-linearity of consumer consumption pattern complex data is taken as input.To minimize the computational cost and complexity of the data,the average of the feature engineering approaches includes:Recursive Feature Eliminator(RFE),Extreme Gradient Boosting(XGboost),Random Forest(RF),and are upgraded to extract the most relevant and significant features.To this end,we have proposed the DensetNet-121 network and Support Vector Machine(SVM)ensemble with Aquila Optimizer(AO)to ensure adaptability and handle the complexity of data in the classification.Further,the AO method helps to tune the parameters of DensNet(121 layers)and SVM,which achieves less training loss,computational time,minimized overfitting problems and more training/test accuracy.Performance evaluation metrics and statistical analysis validate the proposed model results are better than the benchmark schemes.Our proposed method has achieved a minimal value of the Mean Average Percentage Error(MAPE)rate i.e.,8%by DenseNet-AO and 6%by SVM-AO and the maximum accurateness rate of 92%and 95%,respectively.Muhammad Irfan Ali Raza Faisal Althobiani Nasir Ayub Muhammad Idrees Zain Ali Kashif Rizwan Abdullah Saeed Alwadie Saleh Mohammed Ghonaim Hesham Abdushkour Saifur Rahman Omar Alshorman Samar Alqhtani 2022Computers, Materials & Continua2022,,9:2
18Population Variation and Food Habits of Ranid Frogs in the Rice-Based Cropping System in Gujranwala Region,Pakistan显示文摘The current study aims to investigate the population variation and food habits of ranid frogs in the rice-based cropping system in District Gujranwala,Pakistan.The population in the study area was estimated using capture,mark and release method whereas food habits of the species were studied by analysis of stomach contents.The results showed the highest average population was found during August 2009(93.10±18.64/ha) while the lowest from December 2008 to February 2009.Maximum seasonal populations existed in summer 2009,whereas winter 2008 sizes were at a minimum.Stomach content analysis of the species revealed percent frequency(% F) of occurrence of insects(80.3),earthworms(28.5),whole frogs(15.8),bone pieces(22.5),rodents(1.66),vegetation(5.0),soil particles(13.3) and some unidentified material(7.5) in all the stomach samples.Most frequently consumed prey items were insects(30% by volume),although frogs also preyed upon conspecifics and rodents.Insects recovered from the stomach contents were identified as belonging to Orthoptera,Lepidoptera,Coleoptera,Diptera,Odonata and Homoptera as well as the class Archnida.Insects recovered from the stomach contents were compared to those captured from the study area.Saima Yousaf Tariq Mahmood Muhammad Rais Irfan Zia Qureshi 2010Asian Herpetological Research2010,1,2:2
19无贵金属光催化剂VC/CdS纳米线将苯甲醇选择性氧化为苯甲醛并产氢显示文摘太阳能制氢作为一种绿色、实用、可再生的能源生产技术越来越受到人们的关注.传统的光解水产氢通常用三乙醇胺、硫化钠/亚硫酸钠、乳酸、甲醇、抗坏血酸和甲醇等做牺牲剂,这些试剂的加入不仅会污染环境,还会增加制氢成本.而目前完全无牺牲剂体系的产氢效率普遍较低,使得发展经济绿色的牺牲剂体系尤为迫切.通过光催化在单一水性体系中同时生产可储存和可再生的氢气与高附加值的有机化学品是一种新兴环保的策略.本文采用简单的静电自组装和煅烧方法将碳化钒(VC)和CdS纳米线(NW)复合形成VC/CS.结果表明,与原始的CdS NWs相比,负载适量VC的CdS NWs的光催化活性显著提高.然而,同时促进光解水产氢和苯甲醇选择性氧化的机理仍需要进一步探究.X射线衍射谱、高倍透射电子显微镜、扫描透射电子显微镜以及光电子能谱结果表明,VC和CdS NW是紧密结合的,且Cd,S,C和V元素均匀分布,由于两者之间的紧密结合引起了催化剂颜色变化.紫外可见光谱(UV-Vis)结果表明,样品的光吸收范围增大,但吸收带边没有发生明显改变.当采用Na_(2)S·9H_(2)O和Na_(2)SO_(3)做牺牲剂时,VC/CS的产氢活性明显高于Pt负载的CdS,说明VC是一种非常有利于产氢的非贵金属助催化剂.当改用苯甲醇(BO)做牺牲剂时,产氢速率明显增加,同时苯甲醇选择性氧化成苯甲醛(BD).进一步增加VC的负载量,样品产氢活性先增加后减小;当VC的负载量达到15%(VC/CS-15)时,在可见光(λ>420 nm)照射2 h后产氢效率达到20.5 mmol g^(–1) h^(–1),BO转化率为41%,BD选择性超过99%,约为CdS NW的661倍.将光活性测试时间由2 h延长至4 h,BO转化率由41%提高到58%,但BD选择性降至88%.样品VC/CS-15上BD和H_(2)生成趋势与UV-Vis漫反射光谱结果一致,表明反应是通过光催化过程进行的.此外,VC/CS-15在单色420 nm处产生BD和H_(2)的表观量子效率约为7.5%.光催化活性的增强是由于VC的加入降低了样品的Zeta电位,使其对BO具有更强的吸附作用,同时VC在CdS NWs上的牢固附着为质子还原提供了更多的活性位点,通过减少电荷传输距离和提供更宽的电子传输通道来增强光生电子的传输.综上,本文设计的同时产氢和生成高附加值有机化学品的方法光解水产氢提供了新思路.Muhammad Tayyab 刘玉洁 敏世雄 Rana Muhammad Irfan 朱乔虹 周亮 雷菊英 张金龙 2022Chinese Journal of Catalysis2022,43,4:1
20MPLS Unleashed:Remedy Using IPSEC over MPLS VPN显示文摘Syed Noor-ul-Hassan Shirazi Muhammad Asim Muhammad Irfan and Nassar Ikram 2010Communications in Computer and Information Science2010,76,:1
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