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Relationship of Uric Acid with Superoxide Dismutase (Sod) in Induced Hyperuricemic Rat Model

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Pharmacology & Pharmacy 2012年第4期3卷 404-408页

作者： Shiza Batool Iftikhar Ahmed Muhammad Sarwar Hafeez ul hassan Assistant Biochemistry Department Aziz Fatima medical and Dental College Faisalabad Pakistan Professor Biochemistry Department Baqai Medical University Karachi Pakistan Professor Chemical Pathology Department Al Jouf University Kingdom of Saudi Arabia Professor Physiology Department Baqai Medical University Karachi Pakistan.

Increase uric acid levels have been found in oxidative stress. Urate radicals do not react with oxygen to form another peroxy radical, thus increasing the efficacy of uric acid as an antioxidant. Therefore, this study is designed to measure the level of uric acids and find out the relationship of uric acid with superoxide dismutase in induced hyperuricemic model. Forty male albino rats with an average weight of 180 ± 2 g were selected. The rats were grouped. The animals were fed on standard diet and given tap water ad libitum until treatment. Albino rats were divided into four groups. Group A(10)-control given only standard diet, group B(10) fed on 60% fructose with standard diet , group C(10) fed on fructose, standard diet and intraperitonially oxonic acid 250 mg/kg and group D (10) only on injection intraperotonially oxonic acid 250 mg/kg. At the end of study 10 mL of blood was drawn from heart of rats. Then blood was estimated for superoxide dismutase and uric acids done by kit methods randox-manual/Rx monza UA230/UA 233. Results: In Group C superoxide dismutase was found to be 32 % (244 mg/dL ± 2.23) more than control. In the same group the uric acid concentration was highly significantly correlated with control. Conclusion: The uric acid concentration increases when we take fructose up to 60% in our diet. It also increases superoxide dismutase concentration. More than this value may have inverse effect on the uric acid level and its role as an antioxidant may become inversed.

关键词： Uric Acid Superoxide Dismutase Albino Rats Fructose Induced Hyperuricemia

Integration of Remote Sensing and GIS to Assess Vulnerability of Environmental Degradation in North-Western Bangladesh

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Journal of Geographic Information System 2015年第5期7卷 494-505页

作者： Md. Shareful hassan Syed Mahmud-ul-Islam Muhammad Tauhidur Rahman Center for Environmental Change Studies and Management Dhaka Bangladesh Department of Sustainable Development Environmental Science and Engineering KTH-Royal Institute of Technology Stockholm Sweden Department of City and Regional Planning King Fahd University of Petroleum and Minerals Dhahran KSA

Environmental degradation is a burning issue in Bangladesh. The degradation process is extremely acute in the north-western part of Bangladesh due to many environmental and anthropogenic reasons. However, initiative of research work on this issue is very crucial and urgent for regional and local planning and management. In this paper, Nachole and Niamotpur Upazilas were considered as the study area to identify and quantify environmental degradation using an integrated Geographic Information System (GIS) and Remote Sensing (RS) technique. The results of the study reveal that the area is one of the most vulnerable areas in terms of land degradation that already affected local agriculture, biodiversity, water supply and overall socio-economic livelihoods. From the modelling results, about 66,301 hectares (90%) of land are vulnerable to land degradation, of which 24,736, 40,309 and 256 hectares of land were classified as severely, highly, and moderately vulnerable areas respectively. The overall image classification accuracy for all the resultant images was 95.40% while kappa coefficient was 0.94.

关键词： GIS Remote Sensing Landsat DEM Soil Degradation Bangladesh

Role of knowledge economy in managing demand-based environmental Kuznets Curve

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Geoscience Frontiers 2024年第4期15卷 397-410页

作者： Rukhsana Kalim Shajara ul-Durar Mubasher Iqbal Noman Arshed Muhammad Shahbaz Department of Economics and Statistics Dr.Hassan Murad School of ManagementUniversity of Management and TechnologyLahorePakistan University of Sunderland The School of Business ManagementEdinburgh BuildingChester RoadSunderland SR13SDUnited Kingdom Department of Economics Division of Management and Administrative SciencesUniversity of EducationLahorePakistan Department of International Trade and Finance School of Management and EconomicsBeijing Institute of TechnologyBeijingChina Center for Sustainable Energy and Economic Development Gulf University for Science and TechnologyHawallyKuwait

Aggregate demand or supply at equilibrium is commonly used as a representative of the macroeconomic activity of an economy whereby aggregate demand denotes the behaviour of individuals and ***,aggregate demand can also directly affect environmental deterioration via changes in aggregate *** study tried to explore this relationship,known as the demand-based Environmental Kuznets Curve(Demand EKC)and the role of different knowledge economy *** economy indicators are proposed to influence consumption patterns,altering the demand EKC that empirical studies have *** this purpose,secondary data for 147 countries were collected from 2008 to 2018,also classified as *** study found that aggregate demand significantly affects carbon *** long-run results are estimated using the Fully Modified Ordinary Least Square *** factors like renewable energy consumption,population density,and financial development significantly affect carbon emissions in sample *** study has incorporated four pillars of a knowledge-based economy and the results showed that these indicators helped reduce consumption-related CO_(2) emissions.

关键词： Kuznets Curve Knowledge economy Higher education Institutional quality Innovation Technology

通过实验和理论验证Pt0/SrTiO_(3)-δ复合催化剂双反应路径促进CO_(2)还原

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Chinese Journal of Catalysis 2023年第3期46卷 113-124页

作者：李卓根 Qadeer ul hassan 张伟斌朱陆军高健智石先进黄宇刘鹏朱刚强陕西师范大学物理与信息技术学院陕西西安710062 云南师范大学物理和电子信息学院云南昆明650500 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710061

在以H_(2)O为质子源的光催化二氧化碳还原反应(CO_(2)RR)过程中,光解H_(2)O产氢气(H_(2))被认为是一个竞争反应.因此,光催化CO_(2)RR过程需要抑制H_(2)的产生,以提高碳氢产物的选择性和产率.以CO_(2)和H_(2)为反应物的逆水气变换反应(RW... 详细信息

在以H_(2)O为质子源的光催化二氧化碳还原反应(CO_(2)RR)过程中,光解H_(2)O产氢气(H_(2))被认为是一个竞争反应.因此,光催化CO_(2)RR过程需要抑制H_(2)的产生,以提高碳氢产物的选择性和产率.以CO_(2)和H_(2)为反应物的逆水气变换反应(RWGS)是常见的CO_(2)加氢反应,在较高的温度和催化剂作用下生成CO和H_(2)O.目前,光催化CO_(2)RR研究主要聚焦于产物的选择性,而有关光解H_(2)O产生的还原性气体H_(2)在光热效应的促进下成为CO_(2)RR中新的质子源研究较少.光热催化是一种新的高效催化反应方式,在反应过程中需要光照和加热.光照能够促进半导体光生载流子的激发,热效应则能降低反应物分子的活化势垒,并能够促进中间产物的表面迁移以及生成物的脱附.利用光热催化热力学和动力学上的有利条件,为以H_(2)O为质子源的光热催化CO_(2)RR中RWGS反应提供了H_(2)源以及所需的能量.本文合成了具有强电子转移能力、高热稳定性和化学稳定性的Pt纳米颗粒(NPs)负载在具有丰富氧空位(OVs)的SrTiO_(3)-δ纳米片,形成金属-半导体相互作用的Pt-OVs-STO纳米复合催化剂,并利用该纳米复合催化剂系统地研究了以H_(2)O为质子源的光热催化CO_(2)RR的反应路径.结合X射线粉末衍射、X射线光电子能谱、高角度环形暗场和明场球差校正扫描电子显微镜、电子顺磁共振和紫外可见吸收光谱等表征手段,研究了表面负载的Pt^(0)NPs与SrTiO_(3)-δ之间的相互作用.这种金属-半导体之间的强相互作用和独特的电子结构促进了复合半导体结构的光吸收能力,提升了光生载流子的分离以及对反应物分子的吸附.由H_(2)O分解产生的H_(2)能够有效地促进在Pt-OVs-STO纳米复合结构的双路径CO_(2)还原反应:CO_(2)直接质子化和RWGS反应.DFT理论计算结果表明,该纳米复合结构能够有效地促进半导体表面电荷转移和H_(2)生成,并且降低RWGS反应和CO_(2)质子化的反应势垒.综上,本文阐明了在H_(2)O为质子源的光热催化CO_(2)RR中Pt^(0)/SrTiO_(3)-δ纳米复合结构上光解H_(2)O产生的H_(2)和RWGS反应之间的关系,并为后续的CO_(2)RR的研究提供了新视角.

关键词：光热催化析氢反应逆水煤气反应钙钛矿金属-半导体相互作用

Growth, Yield and Quality Performance of Pearl Millet (<i>Pennisetum americanum</i>L.)

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American Journal of Plant Sciences 2014年第15期5卷 2215-2223页

作者： Mahmood ul hassan Azraf-ul-Haq Ahmad Shahid Ibni Zamir Ihtishamul Haq Farhan Khalid Tassadduq Rasool Adil Hussain Department of Agronomy University of Agriculture Faisalabad Pakistan

Livestock industry of Pakistan is expanding day by day. To meet its growing demand high fodder yielding and nutritious varieties of fodder crops are needed. Pearl millet (Pennisetum americanum L.) is an excellent choice for this purpose. In order to explore the possibility of the better yield potential varieties of pearl millet performed in a good manner under agro ecological conditions of Faisalabad during the year 2012. A field experiment was conducted at Agronomic Research Area, University of Agriculture, Faisalabad, Pakistan. Randomized complete block design was used with three replications;the net plot size was 1.8 m × 6 m. The experiment was comprised of nine millet varieties named Cholistani Bajra, Barani Bajra, MB-87, Sargodha Bajra 2011, 18-BY, Super Bajra-1, PARC-MS-2, 86-M-52 and FB-822. All other agronomic practices were kept normal and constant. Data on yield and yield components were recorded by standard procedure. Significant results were recorded among the varieties for forage growth and yield. The variety 86-M-52 produced maximum forage and dry matter yield because of more number of leaves (14), leaf area (3540.1 cm2) followed by Sargodha Bajra-2011. All cultivars have statistically significant differences in respect of quality characteristics. However, non-significant differences were observed among cultivars regarding ash contents. The cultivar Sargodha Bajra-2011 has the highest crude protein (10.347%) and the cultivar FB-822 has the minimum crude protein percentage (6.733%). While PARC-MS-2 has the highest crude fiber percentage (34.667%) but variety MB-87 has the minimum crude fiber (24.333%). Variety 86-M-52 proved better for getting higher forage yield followed by Sargodha Bajra-2011 than all other varieties. Sargodha Bajra-2011 is the best cultivar that performed well in respect of quality parameters under irrigated conditions of Faisalabad.

关键词： Forage Fiber Varieties Quality

多级孔Ti-MOFs负载超细Pd纳米颗粒实现高效光热CO_(2)还原

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Science China Materials 2023年第6期66卷 2317-2328页

作者：吕虹娟 Qadeer ul hassan 范书聪王颖安玉蓉朱刚强蒋育澄袁文玉翟全国 School of Chemistry&Chemical Engineering Shaanxi Normal UniversityXi’an 710062China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China

设计钛基金属有机骨架(MOF)实现高效光催化CO_(2)还原具有重要意义但仍极具挑战.本文发展了一种新的一步原位水蚀刻方法制备超细Pd纳米颗粒/多级孔Ti-MOFs高效光催化剂,其中水刻蚀在形成多级孔结构的同时也为Pd的锚定提供了丰富位点,进... 详细信息

设计钛基金属有机骨架(MOF)实现高效光催化CO_(2)还原具有重要意义但仍极具挑战.本文发展了一种新的一步原位水蚀刻方法制备超细Pd纳米颗粒/多级孔Ti-MOFs高效光催化剂,其中水刻蚀在形成多级孔结构的同时也为Pd的锚定提供了丰富位点,进而在光还原的作用下一步实现Pd纳米颗粒在MOFs表面和内部的负载.得益于多级孔结构和超细Pd颗粒负载,Pd/hMUV-10在350℃光照下的CO产率高达65.9 mmol g^(-1)h^(-1),比目前最先进的MOF基催化剂高出约两个数量级,并超过大多数已报道的无机半导体基催化剂.在200℃相对温和的条件下,CO的产率也达到3.36 mmol g^(-1)h^(-1).在350℃的连续循环测试中,催化剂活性几乎没有衰减.理论计算表明,Pd负载可增强对CO_(2)的吸附和降低CO_(2)还原能垒,从而实现高效光热CO_(2)还原.本文所报道的Pd/hMUV-10催化剂有望在工业CO_(2)捕获和转化中得到应用.

关键词： Pd纳米颗粒多级孔结构光还原无机半导体能垒光催化循环测试

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火灾下受弯钢筋混凝土梁损伤规律研究

火灾下受弯钢筋混凝土梁损伤规律研究

作者：韩石（Haseeb ul hassan）中南大学

学位级别：硕士

火灾作为隧道运营过程中的主要灾害,不但会降低隧道整体的承载力和安全性,还会威胁群众生命财产安全。考虑到隧道多为钢筋混凝土结构,在受到火灾时,钢筋混凝土结构的损伤情况将会直接影响隧道火灾救援及灾后修复工作。因此,研究温度与... 详细信息

火灾作为隧道运营过程中的主要灾害,不但会降低隧道整体的承载力和安全性,还会威胁群众生命财产安全。考虑到隧道多为钢筋混凝土结构,在受到火灾时,钢筋混凝土结构的损伤情况将会直接影响隧道火灾救援及灾后修复工作。因此,研究温度与弯矩耦合作用下钢筋混凝土结构的受力和损伤情况。但由于足尺钢筋混凝土结构的火灾试验的操作难度较高、可重复性不强,通过试验得出结构的热力耦合损伤规律具有一定的限制。随着计算机仿真模拟的不断进步,数值模拟所得结果已经能够很好地贴近于试验结果,同时又因其具有不受试验成本和试块尺寸限制的优势,弥补了试验的不足。因此,本文以足尺钢筋混凝土梁为研究对象,采用试验和数值模拟相结合的方法,通过试验测得梁的基础温度场分布及变形情况,将试验结果与数值模拟结果进行对比分析,验证数值模拟结果的准确性,而后通过ABAQUS建立数值模拟模型,改变模型的受火时间和弯矩大小,研究钢筋混凝土梁在火灾和弯矩耦合下的温度场分布及结构变形规律。本试验的燃烧炉为中南大学防灾科学与安全技术研究所自行研制的大型电阻炉,该试验炉的炉膛净空为宽420mm,高470 mm。试验炉体总长3700mm,超过试件截面高度的4倍,可使\试件受到一致温度场的作用。试验炉由炉箱结构、加热元件、隔热层、附件组成。炉箱结构由角钢和扁钢焊接成骨架,外面覆盖薄钢板,用以支撑并固定炉瓦和隔热材料,成为一个刚性的整体。加热元件的主要部件是炉瓦,选用耐火材料制成的定型井式炉瓦加工而成,在炉瓦的外侧至炉箱之间,用硅酸铝耐火纤维保温材料填充,作为隔热层。炉箱两端的下方有槽钢相连,共有4个吊环,便于吊装和悬挂;炉箱一侧的上部有电阻丝接线端,可接入电源;炉箱中部有3个温度测控,可以插入热电偶,以便实时监控温度,温度控制柜中采用了继电器控制电路。电源通过控制柜接入试验炉,构件的试验炉和温度控制柜在制作完成后一起使用,能测量到炉内各个热电偶的升温曲线,多次的高温试验的升温曲线恒定,且再现性好。论文的研究工作主要从以下几个方面开展:一、钢筋混凝土试验梁的制备与加载、测温试验。根据已有的研究和理论分析,影响钢筋混凝土梁火灾损伤程度的主要因素有构件初始荷载、燃烧时间、构件配筋及保护层厚度等。由于试验条件和时间的限制,本次试验的对比因素只考虑初始荷载、燃烧时间、配筋率的影响。本试验共设计钢筋混凝土梁7根,梁的截面尺寸为:宽250 mm,高400mm,梁长4800mm,采用单筋矩形截面。纵向受力钢筋采用直径为22mm,HRB400级的热轧钢筋,数量依据试验需要进行调整;假设构件处于室内正常环境,保护层厚度为25mm;混凝土强度等级为C40;架立钢筋采用2根直径为10mm,HPB235级热轧钢筋;箍筋采用四边形封闭箍筋,直径为8mm,HPB235级热轧钢筋。混凝土强度按水泥:水:砂:碎石=1:0.56:2.15:4.06的配合比设计,水泥采用湖南省韶峰水泥集团有限公司生产的强度等级为42.5的普通硅酸盐水泥;砂采用湘江河砂(中砂);卵石采用湘江的卵石、最大粒径为25mm。首先试验梁按要求就位,采用千斤顶对试验梁加载。试验采用分级加载,每级荷载为20k N,且加完一级荷载后,稳定2分钟再读数。将高温冷却后的钢筋混凝土梁进行静力加载试验,研究其破坏形式以及剩余承载力的大小,试验过程与未受高温的梁静力加载试验相似。为测定高温试验时梁截面的内部温度场分布,在其内部预埋铜管以插入热电偶。构件制作时,在每根根梁的1/4、跨中和3/4截面内部均预埋了铜管。并且1/4截面的铜管预埋在第一根钢筋上面,埋置5根,高度均匀分配,同样,3/4截面的铜管预埋在第二根钢筋上面,埋置5根,高度均匀分配,跨中截面的铜管预埋在跨中,埋置8根。二、构建钢筋混凝土梁的数值模拟模型。考虑到试验结果存在一定的离散型及随机性,较难通过定量调整影响梁损伤结果的参数,获取钢筋混凝土梁的损伤规律。将试验结果与数值模拟结果进行对比分析,验证数值模拟结果的准确性,而后通过数值模拟调整受火时间及荷载数值,可得出钢筋混凝土梁在热力耦合作用下的变形损伤规律,为合理判定火灾后钢筋混凝土构件的损伤评估及修复工作提供依据。ABAQUS是一套功能强大的有限元模拟软件,可以对复杂的固体力学问题及结构力学系统进行分析,对单一零件及多物理场的力学问题均适用,尤其善于处理高度非线性模拟问题。ABAQUS丰富的单元库可以模拟任意几何形状,其内含有的材料模型库可以模拟大多数典型的工程材料性能,如混凝土、可压缩泡沫以及地质材料如土壤和岩石等。钢筋混凝土梁模型的建立分为八个模块,具体如下:(1)创建部件空间钢筋混凝土连续梁,模型是由混凝土、纵筋、箍筋和刚性垫块等部件组成,所有部件均采用C3D8单元。混凝土梁的尺寸为宽250 mm,高400mm,梁长4800mm,纵向受力钢筋采用直径为22mm,箍

关键词：钢筋混凝土梁火灾弯矩热力耦合

Fuzzy Synthetic Evaluation Model for Smart Washing Machine

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American Journal of Operations Research 2023年第4期13卷 93-109页

作者： Samsun Nahar Marin Akter Khadiza Begum Mahede ul hassan Md. Abdul Alim Department of Basic Sciences and Humanities University of Asia Pacific Dhaka Bangladesh General Education Department City University Dhaka Bangladesh Computer Science and Engineering Department Prime University Dhaka Bangladesh Department of Mathematics and Statistics Bangladesh University of Business and Technology Dhaka Bangladesh Department of Mathematics Bangladesh University of Engineering and Technology Dhaka Bangladesh

Generally fuzzy control system (FCS) is worked in washing machine. For the fuzzy set theory, membership functions are the building blocks. In a fuzzy set, fuzziness is determined by its membership functions. The shapes of membership functions are important, because it has an effect on fuzzy inference system. The shapes of membership functions can be triangular, trapezoidal and gaussian. The most widely used triangular membership function is used in this paper, because it can capture the short time period. In washing machine, open loop control system is found. This paper applies a fuzzy synthetic evaluation method (FSEM) for washing cloth in washing machine as FSEM can handle the multiple criteria with the help of evaluation matrix generated from membership function and weight matrix generated by Analytical Hierarchy Process (AHP). The purpose of this research is to minimize the wash time. By applying FSEM, we get a wash time which is less than that wash time got from applying the Mamdani approach in FCS. An example is given for illustration. For more reduction of wash time, statistical averaging method is also used. To reduce the wash time, statistical averaging method can be used in Mamdani approach also.

关键词： Fuzzy Control System Fuzzy Synthetic Evaluation Method Analytic Hierarchy Process Method Mamdani Approach Statistical Averaging Method

Acylhydrazide and Isatin Schiff Bases as Alternate UV-Laser Desorption Ionization (LDI) Matrices for Low Molecular Weight (LMW) Peptides Analysis

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American Journal of Analytical Chemistry 2012年第12期3卷 779-789页

作者： Syed Ghulam Musharraf Aisha Bibi Najia Shahid Muhammad najam-ul-Haq Momin Khan Muhammad Taha Uzma Rasool Mughal Khalid Mohammed Khan Department of Chemistry Bahauddin Zakariya University Multan Pakistan Hussain Ebrahim Jamal Research Institute of Chemistry International Center for Chemical and Biological Sciences University of Karachi Karachi Pakistan Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological Sciences University of Karachi Karachi Pakistan

Matrix-assisted laser desorption/ionization (MALDI) is a preferred and widely used mass spectrometric technique for the analysis of macromolecules. Limited UV-LDI matrices are available for the analysis of biomolecules due to the restricted structural features to serve in the laser desorption/ionization mechanism with a problem of background signals appearing in the low mass region. This paper describes the application of Schiff base derivatives of acylhydrazide and isatin as alternate UV-LDI matrices for the analysis of peptides with significantly low background signals. Thirty one compounds have been successfully employed as matrices for the analysis of low molecular weight (LMW) peptides (α-Cyano-4-hydroxycinnamic acid (HCCA), a preferred choice for peptide analysis.

关键词： MALDI-MS LDI Matrix Acylhydrazide Schiff Bases Bis-Schiff Bases of Isatin Schiff Bases of Isatin Peptides