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Chinese Chemical Letters 2016年第1期27卷 104-108页

作者： Nader Ghaffari Khaligh Sharifah Bee Abd Hamid salam j.j.titinchi Nanotechnology & Catalysis Research Centre NANOCAT University Malaya Department of Chemistry University of the Western Cape

N-Methylimidazolium perchlorate（[MIm]ClO_4） was synthesized and some of its physico-chemical properties, such as density, surface tension were investigated. A thermo gravimetric analysis（TGA） and solvent performance were also studied. The results show that this ionic liquid is an excellent catalyst for the synthesis of 4,4＇-（arylmethylene）bis（1H-pyrazol-5-ol） derivatives under solvent-free *** method has the advantages of high yield, clean transformation, simple operation and short reaction time. The ionic liquid can be recycled without significant loss of activity.

关键词： Ionic liquid N-Methylimidazolium perchlorate Bis(pyrazol-5-ol)s Recycle

Enhancement of oxygen reduction activity and stability via introducing acid-resistant refractory Mo and regulating the near-surface Pt content

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journal of Energy Chemistry 2020年第12期29卷 246-252页

作者： Shouquan Feng jiajia Lu Lin Luo Guangfu Qian jinli Chen Hanna SAbbo salam jjtitinchi Shibin Yin College of Chemistry and Chemical Enginering.School of Physical Science and Technology.Key Laboratory of New Processing Technology for Nonferrous Metals and Materials State Key Laboratory of Processing for Non Ferrous Metal and Featured MaterialsGuangxi UniversityNanning 530004.GuangxiChina Department of Chemitry University of the Western Cape7535 Cape TownSouth Africa

Although Pt Ni catalyst possesses good oxygen reduction activity, its poor stability is the main obstacle for the commercialization of proton exchange membrane fuel cells(PEMFCs). In this work, we introduce the acid-resistant refractory Mo to enhance the structure stability and modify the electronic structure of Pt in the prepared PtNi catalyst, improving the catalytic activity for oxygen reduction reaction(ORR). In addition, near-surface Pt content in the nanoparticle is also optimized to balance the ORR activity and stability. The electrochemical results show that the alloy formed by Mo and Pt Ni is obviously more stable than the PtNi alloy alone, because the acid-resistant Mo and its oxides effectively prevent the dissolution of Pt. Especially, the Pt3 Ni3 MoN/C exhibits the optimal ORR catalytic performance in O2-saturated 0.1 mol L^(-1) HClO4 aqueous solutions, with mass activity(MA) of 900 m A mg^(-1) Pt at 0.90 V vs. RHE, which is 3.75 times enhancement compared with the commercial Pt/C(240 mA mg^(-1) Pt). After 30 k accelerated durability tests, its MA(690 m A mg^(-1) Pt) is still 2.88 times higher than the pristine Pt/C. This study thus provides a valuable method to design stable ORR catalysts with high efficiency and has great significance for the commercialization of PEMFCs.

关键词： Oxygen reduction reaction Surface platinum content regulate Ternary alloy catalyst Activity Stability

An efficient energy-management strategy for a DC microgrid powered by a photovoltaic/fuel cell/battery/supercapacitor

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Clean Energy 2022年第6期6卷 827-839页

作者： Furqan A.Abbas Adel A.Obed Mohammed A.Qasim salam j.Yaqoob Seydali Ferahtia Department of Electrical Engineering Electrical Engineering Technical CollegeMiddle Technical UniversityBaghdad 10001Iraq Department of Nuclear Power Plants and Renewable Energy Sources Ural Federal University19 Mira St620002 YekaterinburgRussia Department of Projects and Engineering Services Ministry of HealthBaghdad 10001Iraq Department of Research and Education Authority of the Popular CrowdPrime MinisterBaghdad 10001Iraq Laboratore d’Analyse des Signaux et Systemes Department of Electrical EngineeringUniversity of M’silaMsila 28000Algeria

The outcome of this paper is to suggest an efficient energy-management strategy(EMS)for a direct-current(DC)microgrid(MG).The typical MG is composed of two renewable energy sources[photovoltaic(PV)systems and fuel cells(FCs)]and two energy-storage elements(lithium-ion battery and supercapacitor).An EMS was proposed to ensure optimal bus voltage with a power-sharing arrangement between the load and the *** a result,in the suggested DC MG,non-linear flatness control theory was used instead of the traditional proportional-integral control *** suggested EMS is intended to supply high power quality to the load under varying load conditions with fluctuating solar irradiation while considering the FC *** validate and prove the effectiveness of the proposed EMS,a MATLAB®environment was *** addition,the output power of the PV system was maximized using the particle swarm optimization algorithm as a maximum power point tracking(MPPT)technique to track the MPP of the 3000-W PV system under different irradiance *** results show that the suggested EMS delivers a stable and smooth DC bus voltage with minimum overshoot value(0.1%)and improved ripple content(0.1%).As a result,the performance of the DC MG was enhanced by employing the flatness control theory,which provides higher power quality by stabilizing the bus voltage.

关键词： photovoltaic fuel cell lithium energy management flatness control supercapacitor non-linear control

Ti_(3)AlC_(2) coated D-shaped fiber saturable absorber for Q-switched pulse generation

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Optoelectronics Letters 2022年第8期18卷 468-471页

作者： Suziana Omar salam MAzooz Ahmad Haziq Aiman Rosol Zulzilawati jusoh Baktiar Musa Sulaiman Wadi Harun School of Electrical Engineering College of EngineeringUniversiti Teknologi MARADungun 23000Malaysia Department of Communication Engineering Engineering Technical CollegeAl-Furat Al-Awsat Technical UniversityNajafIraq Department of Electrical Engineering University of MalayaKuala Lumpur 50603Malaysia Department of Engineering Faculty of Advanced Technology and MultidisciplineAirlangga UniversitySurabayaIndonesia Department of Physics Faculty of Science and TechnologyAirlangga UniversitySurabayaIndonesia

In this letter,a titanium aluminum carbide(Ti_(3)AlC_(2))coated D-shaped fiber is proposed and demonstrated as a new saturable absorber(SA)for Q-switched laser pulse *** preparing the SA,the TiAlCpowder is dispersed in liquid polyvinyl alcohol(PVA)before the solution is dropped and left to dry onto a polished surface of D-shape *** SA is added to an erbium-doped fiber laser(EDFL)cavity to modulate the cavity loss for *** Q-switched laser is obtained at 1561 *** pulse width of the pulses can be varied between 7.4μs and 5.1μs with a corresponding repetition rate range from 41.26 k Hz to 54.35 k Hz,when the pump power is increased from 42.2 m W to 71.5 m *** 71.5 m W pump,the pulse energy is obtained at 70.3 n *** signal-to-noise ratio(SNR)of the fundamental frequency is recorded at 67 d B,which indicates the stability of the laser.

关键词： switched fiber pulse

Conceptual design,modeling and compliance characterization of a novel 2-DOF rotational pointing mechanism for fast steering mirror

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Chinese journal of Aeronautics 2020年第12期33卷 3564-3574页

作者： Muhammad ABID jingjun YU Yan XIE Abdus salam Robotics Institute School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100083China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

In this paper,a novel 2-DOF rotational pointing mechanism(RPM)is designed inspired by the guidelines of the graphical *** mechanism integrates with a fast steering mirror(FSM)for compensating pointing errors of a laser *** design intends to achieve an angular travel of±10 mrad and steers a 25 mm mirror aperture.A planar flexure with beam flexures accompanied in parallel with an axial flexure build-up mechanism *** mechanismbased RPM ensures high precision and *** characteristics are established based on the stiffness matrix method for four different planar flexure *** layout with best in-plane rotational compliance is then assessed for performance sensitivity to mechanism dimension parameters and parasitic error,thus informing the design *** stiffness in both the inplane rotational axes and stress is determined based on finite element analysis(FEA).The wire electrical discharge machining(EDM)is employed for developing the proof of concept for the RPM and is then assembled in *** are conducted to determine the rotational stiffness and angular travel about both in-plane rotational *** among theoretical,numerical and experiments reveal excellent linearity of rotational stiffness along the rotational travel *** maximum theoretical error is less than 5.5%compared with FEA while,the experimental error has a mean of 5%and 3%for both rotational axes thus satisfying the intended design requirement.

关键词： Compliant mechanism Finite element analysis Graphical approach Rotational stiffness Sensitivity analysis

Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest USA

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Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed Abd salam EL-VILALY Kamel DIDAN Stuart E. MARSH Willem j.D. VAN LEEUWEN Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA Arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA Department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized Difference Vegetation Index （NDVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NDVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

滨鹬马蹄吸虫(复殖目:微茎科)的尾蚴和囊蚴期的季节动态(英文)

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动物学报 2007年第3期53卷 463-469页

作者： M. A. AL-KANDARI j. M. ABDUL-salam M. A. MOUSSA B. S. SREELATHA Department of Biological Sciences Faculty of Science Kuwait University P.O. Box 5969 Safat 13060 Kuwait Department of Community Medicine and Behavioral Sciences Faculty of Medicine Kuwait University P.O. Box 24923 Safat 13110 Kuwait

对科威特湾微茎科滨鹬马蹄吸虫幼虫期的中间宿主双带盾桑椹螺(Clypeomorus bifasciata)及小相手蟹(Nanosesarma minutum)的季节动态进行了研究。调查期超过一年,在检查的1 600只螺和415只蟹中, 11.8 %的螺感染了8种马蹄属线虫中的一种,... 详细信息

对科威特湾微茎科滨鹬马蹄吸虫幼虫期的中间宿主双带盾桑椹螺(Clypeomorus bifasciata)及小相手蟹(Nanosesarma minutum)的季节动态进行了研究。调查期超过一年,在检查的1 600只螺和415只蟹中, 11.8 %的螺感染了8种马蹄属线虫中的一种,且以滨鹬马蹄吸虫的感染占优势(9.9 %螺感染) ; 80 %的蟹感染滨鹬马蹄吸虫囊蚴。虽然一年四季两种宿主都会感染,但吸虫的流行和尾蚴(指成熟期感染)在夏季呈现高蜂。从螺体排出的尾蚴具有明显季节性,在此海湾必须要超过最低温度20℃。总的感染率在较大(较老)的螺里有所下降,显示吸虫影响宿主生存并随之影响宿主群体结构。囊蚴的感染丰度与蟹的个体大小有明显相关性;较大的蟹感染较多的囊蚴,显示宿主能耐受更多的吸虫。调查显示,囊蚴的感染率与蟹的大小或性别无相关性。囊蚴体外脱囊以及产卵吸虫的释放证明,成熟虫体终年存在于所有大小和性别不同的蟹里,显示从蟹到鸟的持续感染是可能的。总的来说,滨鹬马蹄吸虫在海湾的传播动态是由这两种无脊椎动物宿主来协调,并似乎是被一系列依赖于温度的活动控制,这些活动影响易感宿主种群及感染性幼虫期尾蚴和囊蚴的存在。

关键词：滨鹬马蹄吸虫双带盾桑椹螺小相手蟹科威特尾蚴囊蚴种群动态

肠毒素P基因SEP在大肠杆菌中的表达、蛋白纯化与鸡抗体制备

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肠毒素P基因SEP在大肠杆菌中的表达、蛋白纯化与鸡抗体制备

作者： Walaa Abduljalil Ali salam Al-Mathagi 兰州理工大学

学位级别：硕士

金黄色葡萄球菌肠毒素(SEs)是金黄色葡萄球菌在生长的对数期或从指数期向稳定期过渡期间合成的有效胃肠外毒素。金黄色葡萄球菌可产生多种胃肠毒素,包括金黄色葡萄球菌肠毒素A、B、C、D、E、F、G、H、I、j、K、L、M、N、O、P等多种肠毒... 详细信息

金黄色葡萄球菌肠毒素(SEs)是金黄色葡萄球菌在生长的对数期或从指数期向稳定期过渡期间合成的有效胃肠外毒素。金黄色葡萄球菌可产生多种胃肠毒素,包括金黄色葡萄球菌肠毒素A、B、C、D、E、F、G、H、I、j、K、L、M、N、O、P等多种肠毒素。金黄色葡萄球菌肠毒素P(SEP)是导致食物中毒的主要因素之一。食物尤其是肉制品和乳制品可因处理不当或在高温下储存而被金黄色葡萄球菌污染。SEP中毒症状发病迅速,病人恶心和剧烈呕吐,伴有或不伴有腹泻。鉴于SEP检测在食品安全方面的重要性,本研究亚克隆了SEP基因至大肠杆菌表达载体、表达、纯化、免疫产蛋鸡并制备了鸡卵黄抗体。以期建立基于免疫学方法检测SEP的相关试剂。本论文的主要研究成果如下:(1)以pUC18-SEP为模板DNA,以Primer F(含EcoRI位点)和Primer R(含SalI位点)为引物扩增了SEP基因。扩增产物经EcoRI和SalI酶切、琼脂糖凝胶电泳分离、回收后与相应限制性内切酶处理的pET28a载体连接,获得pET28a-SEP重组载体。经核苷酸序列分析,亚克隆的SEP基因序列与模板和NCBI数据库中的SEP序列一致。(2)含重组质粒pET28a-SEP的大肠杆菌(*** Rossita)活化后在37℃、220rpm下培养至OD≥0.6,之后在16℃、220rpm下以1mmol/L IPTG诱导过夜。离心收集菌体,超声破碎后进行SDS-PAGE分析。结果表明,SEP蛋白主要以可溶性蛋白形式存在于菌体破碎后的上清中,沉淀中仅有少量SEP蛋白。(3)以商品化SEP抗体检测上述大肠杆菌诱导表达后的蛋白,发现诱导表达量最大的蛋白带(32.6k Da)呈阳性。其与含有标签肽(6x His-Thrombin-T7 Tag)的SEP蛋白的理论分子量(29.77k Da)基本一致。(4)上述细胞裂解液上清以Ni-NTA亲和层析法进行了纯化。纯化后的样品进行SDS-PAGE分析,显示分子量在32.6k Da的蛋白被纯化保留。(5)根据SDS-PAGE结果,Ni-NTA纯化的重组SEP蛋白中仍然存在一些微量的杂蛋白。据此,我们以Sephadex G-100进行了进一步纯化,随后以50%的饱和硫酸铵进行了选择性沉淀,进一步提高了重组蛋白SEP的纯度。(6)经Ni-NTA亲和层析纯化后,从SDS-PAGE凝胶中切下分子量为32.6k Da蛋白的条带做串联质谱鉴定。串联质谱共测得8条肽段的氨基酸残基序列,均与重组SEP蛋白的序列一致。(7)每毫克纯化的重组SEP蛋白与完全弗氏佐剂混合后免疫产蛋鸡三次,每次间隔15天。Dot Blotting分析初步表明,在第二次注射抗原后,IgY活性最高。

关键词：金黄色葡萄球菌肠毒素P 基因重组蛋白表达 Ni-NTA亲和层系鸡卵黄抗体

History of Vitamin A Supplementation Reduces Severity of Diarrhea in Young Children Admitted to Hospital with Diarrhea and Pneumonia

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Food and Nutrition Sciences 2013年第2期4卷 150-155页

作者： Mohammod j. Chisti Mohammed A. salam Abu S. G. Faruque Hasan Ashraf Pradip K. Bardhan Sumon K. Das Sayeeda Huq Fahmida Chowdhury Shoeb B. Islam Tahmeed Ahmed Centre for Communicable Diseases (CCD) Dhaka Bangladesh. Centre for Nutrition & Food Security (CNFS) International Centre for Diarrhoeal Disease Research Dhaka Bangladesh Centre for Nutrition & Food Security (CNFS) International Centre for Diarrhoeal Disease Research Dhaka Bangladesh&Clinical Services (CS) Dhaka Bangladesh Centre for Nutrition & Food Security (CNFS) International Centre for Diarrhoeal Disease Research Dhaka Bangladesh&Clinical Services (CS) Dhaka Bangladesh Centre for Nutrition & Food Security (CNFS) International Centre for Diarrhoeal Disease Research Dhaka Bangladesh Clinical Services (CS) Dhaka Bangladesh Clinical Services (CS) Dhaka Bangladesh Research Administration Services (RAS) Dhaka Bangladesh

Background: Although the role of vitamin A in childhood pneumonia in association with diarrhea is not fully proven, we did not find any published data demonstrating the impact of lack of vitamin A supplementation in under-five children who present with the co-morbidities of pneumonia and diarrhea. This study examined whether previous vitamin A supplementation was associated with reduced severity and duration of diarrhea and pneumonia for children presenting with both illnesses. Methods: All admitted children (n = 189) aged 0 - 59 months to the Special Care Ward of the Dhaka Hospital of icddr,b with diarrhea and radiological pneumonia from September-December 2007 were enrolled. We compared clinical features of the children who received (n = 96) and did not receive (n = 93) high potency capsule vitamin A supplementation during previous immunization according to EPI schedule. Results: In logistic regression analysis, after adjusting for potential confounders such as respiratory rate, lower chest wall in-drawing, severe wasting and systolic blood pressure, vitamin A non-supplemented children with pneumonia and diarrhea more often presented in their early infancy (95% CI 1.01 - 1.09), had duration of diarrhea for >4 days (95% CI 1.79 - 11.88), had clinical dehydration (95% CI 1.2 - 5.63), and more often required hospitalization for >7 days (95% CI 1.03 - 8.87). But, there was no significant difference in the clinical features of pneumonia, such as history of cough, respiratory rate, lower chest wall in-drawing, nasal flaring, head nodding, grunting respiration, cyanosis, and inability to drink between the groups. Conclusion: Lack of vitamin A supplementation in under-five children with radiological pneumonia and diarrhea is independently associated with young infancy, duration of diarrhea for >4 days, dehydration and hospitalization for >7 days which underscores the importance of routine supplementation of vitamin A in young infancy. However, lack of vitamin A supplement

关键词： Bangladesh Diarrhea Children Lower Chest Wall In-Drawing Pneumonia Vitamin A Supplementation

BiFeO_(3) codoping with Ba,La and Ti:Magnetic and structural studies

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journal of Advanced Dielectrics 2015年第4期5卷 53-60页

作者： O.García-Zaldívar S.Díaz-Castañón F.j.Espinoza-Beltran M.A.Hernández-Landaverde G.López j.Faloh-Gandarilla F.Calderón-Piñar Facultad de Física-Instituto de Ciencia y Tecnología de Materiales Universidad de La Habana San Láazaro y L VedadoLa Habana 10400Cuba CINVESTAV-Unidad Querétaro Libramiento Norponiente No.2000 Real de JuriquillaQuerétaroQro.76230México Instituto Latino-Americanode Ciênciasda Vidaeda Natureza Universidade Federalda Integração Latino-Americana (ILCVN-UNILA)Avenida Tancredo NevesPTIBloco 6 CEP:85866-000-Foz do Iguaçu-ParanaBrazil División Materiales Avanzados Instituto Potosinode Investigación Científica Tecnológica San Luis Potosí CP78216Méexico

Conventional solid state reaction method,from oxides and carbonates,was employed to prepare bismuth(Bi)-based multiferroic *** undoped BiFeO_(3)(BFO)and the codoped system with Ba,La and Ti(Bi_(1-x)Ba_(x)Fe_(1-y)Ti_(y)O_(3),Bi_(1-x-z)Ba_(x)LazFe_(1-y)TiyO_(3))with x,y,z=0.1 were prepared stoichiometrically and sintered at two different *** structural and magnetic properties were investigated at room *** measurements confirm the obtaining of the rhombohedral perovskite structure of the BFO family *** the undoped system,some reflections of undesired phases are present for two different sintering temperatures,while for the doped system only one phase is present for both *** magnetic characterization at room temperature revealed remarkable differences between the ceramic *** results show that for undoped BFO system,spontaneous magnetization is not observed at room ***,in doped one,a well-defined ferromagnetic behavior is observed at room temperature,possible,due to the suppression of the spatially modulated spin structure of BFO promoted by the reduction of the rhombohedral distortion and the weakening of the Bi-O *** XPS results confirm the presence of oxygen vacancies and the coexistence of Fe^(3+)and Fe^(2+) in all the studied *** measurements reveal that the dopant incorporation has not a direct effect in Neel temperature but possibly yes in ferroelectric-paraelectric transition.

关键词： Multiferroics XPS magnetic bismuth ferrite BiFeO_(3)