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Impact of the Brink-Axel hypothesis on unique first-forbiddenβ-transitions for r-process nuclei

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Chinese Physics C 2024年第3期48卷 148-168页

作者： Fakeha farooq Jameel-Un Nabi Ramoona Shehzadi Department of Physics University of the PunjabQuaid-e-Azam Campus 54590LahorePakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

Key nuclear inputs for the astrophysical r-process simulations are the weak interaction ***,the accuracy of these inputs directly affects the reliability of nucleosynthesis *** majority of the stellar rates,used in simulation studies are calculated by invoking the Brink-Axel(BA)*** BA hypothesis assumes that the strength functions of all parent excited states are the same as for the ground state,only shifted in ***,the BA hypothesis has to be tested against microscopically calculated state-by-state *** this project,we study the impact of the BA hypothesis on calculated stellarβ^(-)-decay and electron capture *** investigation include both unique first forbidden(U1F)and allowed transitions for 106 neutron-rich trans-iron nuclei([27,77]≤[Z,A]≤[82,208]).The calculations were performed using the deformed proton-neutron quasiparticle random-phase approximation(pn-QRPA)model with a simple plus quadrupole separable and schematic ***-point and several key r-process nuclei lie within the considered mass region of the nuclear *** computed electron capture andβ^(-)-decay rates using two different prescriptions for strength *** was based on invoking the BA hypothesis and the other was the state-by-state calculation of strength functions,under stellar density and temperature conditions([10,1]≤[ρYe(g/cm^(3)),T(GK)]≤[10^(11),30]).Our results show that the BA hypothesis invoked U1Fβ^(-)rates are overestimated by 4–5 orders of magnitude as compared to microscopic *** capture rates,more than two orders of magnitude differences were noted when applying the BA *** was concluded that the BA hypothesis is not a reliable approximation,especially forβ^(-)-decay forbidden transitions.

关键词： Brink-Axel hypothesis pn-QRPA model unique first forbiddenβ-transitions GT strength functions trans-iron nuclei r-process

基于UHPLC-QTOF-MS/MS技术的骆驼蓬化学成分分析及其神经保护活性

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中草药 2022年第6期53卷 1688-1696页

作者：王宁宁魏冠华张智军房建国 Mohammad umar farooq Imtiaz Ahmad Qamar 刘映前杨志刚兰州大学药学院甘肃兰州730000 兰州大学化学化工学院甘肃兰州730000 巴基斯坦农业研究中心巴基斯坦伊斯兰堡

目的基于UHPLC-QTOF-MS/MS技术对骆驼蓬Pegannum harmala化学成分进行分析,并探讨其神经保护活性。方法色谱柱为ACQUITY UPLC BEH C_(18)(100 mm×2.1 mm,1.6μm),流动相为0.1%甲酸水溶液(A)-0.1%甲酸乙腈溶液(B),梯度洗脱;体积流量0.... 详细信息

目的基于UHPLC-QTOF-MS/MS技术对骆驼蓬Pegannum harmala化学成分进行分析,并探讨其神经保护活性。方法色谱柱为ACQUITY UPLC BEH C_(18)(100 mm×2.1 mm,1.6μm),流动相为0.1%甲酸水溶液(A)-0.1%甲酸乙腈溶液(B),梯度洗脱;体积流量0.3 mL/min;进样体积2μL;柱温35℃。质谱系统采用电喷雾离子源(ESI),正离子模式下检测。利用过氧化氢(H_(2)O_(2))和6-羟基多巴胺(6-hydroxydopamine,6-OHDA)诱导的PC12细胞氧化损伤模型和脂多糖(lipopolysaccharide,LPS)诱导的BV2细胞神经炎症模型,探讨骆驼蓬全草和种子的甲醇提取物以及去氢骆驼蓬碱、骆驼蓬碱、哈尔满和去甲哈尔满4种骆驼蓬中主要生物碱的神经保护活性。结果从骆驼蓬中共鉴别32个化学成分,全草中主要含有脱氧鸭嘴花碱、鸭嘴花醇等喹唑酮类生物碱,而种子中主要含有去氢骆驼蓬碱、骆驼蓬碱等β-咔啉类生物碱。骆驼蓬全草、种子甲醇提取物和4种生物碱对LPS刺激诱导BV2细胞一氧化氮(NO)生成具有一定的抑制活性,并对H_(2)O_(2)和6-OHDA诱导的PC12细胞损伤均具有明显的保护作用(P<0.01)。结论骆驼蓬全草和种子中的生物碱成分存在差异,而且其所含的生物碱类化合物具有一定的神经保护作用,为骆驼蓬的质量控制及药效物质基础研究提供了参考。

关键词：骆驼蓬 UHPLC-QTOF-MS/MS 生物碱神经保护活性去氢骆驼蓬碱骆驼蓬碱哈尔满去甲哈尔满

Bioassay-guided isolation of novel and selective urease inhibitors from Diospyros lotus

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Chinese Journal of Natural Medicines 2017年第11期15卷 865-870页

作者： Abdur Rauf Ghias Uddin Bina S. Siddiqui Ajmal Khan umar farooq Farhan A. Khan Syed Majid Bukhari Sher Bahadar Khan Department of Chemistry University ofSwabi Anbar-23561 Khyber Pakhtunkhwa Pakistan Institute of Chemical Sciences University ofPeshawar Peshawar-25120 Pakistan H.E.J. Research Institute of Chemistry International Center for Chemical and Biological Sciences University ofKarachL Ka- rachi- 75270 Pakistan Department of Chemistry COMSAT Institute of Information Technology Abbottabad-22060 Pakistan UoN Chair of Oman 's Medicinal Plants and Marine Natural Products University ofNizwa Birkat Al-Mouz Nizwa-616 Oman Center of Excellence for Advanced Materials Research (CEAMR) Department of Chemistry Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Kingdom

Two new dimeric naphthoquinones, 5′,8′-dihydroxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(1; Di-naphthodiospyrol D) and 5′,8′-dihydroxy-5,8-dimethoxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(2; Di-naphthodiospyrol E), along with known naphthoquinones diospyrin(3) and 8-hydroxy diospyrin(4) were isolated from the chloroform fraction of extract of Diospyros lotus roots. Their structures were elucidated by advanced spectroscopic analyses, including HSQC, HMBC, NOESY, and J-resolved NMR experiments. The fractions and compounds 1-4 were evaluated for urease activity and phosphodiesterase-Ⅰ, carbonic anhydrase-Ⅱ and α-chymotrypsin enzyme inhibitory activities. Compounds 1 and 2 and their corresponding fractions showed significant and selective inhibitory effects on urease activities. The IC_(50) values of 1 and 2 were 260.4 ± 6.37 and 381.4 ± 4.80 μmol·L-1, respectively, using thiourea(IC_(50) = 21 ± 0.11 μmol·L^(-1)) as the standard inhibitor. This was the first report demonstrating that the naphthoquinones class showed urease inhibition.

关键词： Diospyros lotus Naphthoquinones Phosphodiesterase-Ⅰ Carbonic anhydrase-Ⅱ α-Chymotrypsin Urease inhibitory activities

Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites

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Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 859-870页

作者： Abid Ali Khan Nafees Bacha Bashir Ahmad Ghosia Lutfullah umar farooq Russell John Cox Department of Chemistry.COMSATS Institute of Information Technology Centre of Biotechnology and Microbiology University of Peshawar Department of Chemistry.COMSATS Institute of Information Technology Abbottabad School of Chemistry University of Bristol Cantock's Close

Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary *** have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory *** fungi have been engineered for the desired secondary metabolites by using different laboratory techniques,for example,homologous and heterologous *** review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites:also the biosynthetic pathways of the bio-organic-molecules were reported.

关键词： Fungi Natural products Microbiology Molecular genetics Chemical biolog

Performance of Rigid Steel Frames under Adequate Soil Conditions Using Seismic Code Provisions

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Open Journal of Civil Engineering 2018年第2期8卷 91-101页

作者： Muhammad Tayyab Naqash Qazi umar farooq Department of Civil Engineering Faculty of Engineering Islamic University of Madinah Medina Kingdom of Saudi Arabia

This study is focused on?nonlinear analysis and design of?spatial and perimeter moment resisting frames for a 9-storeys?office building?having?9.15?m span.?Seismic?design criteria of Eurocode 8?Ductility Class High (DCH)?with behavior factor (q) of 6.5 and AISC/ASCE code,?Special Moment resisting Frame (SMF) with response modification factor (R) of 8 were employed.?The design outcomes?are?expressed in terms of frame performance?(non-linear analysis), section profiles?(code recommendations), strength-demand to capacity ratios, drift-demand to capacity?ratios and structural weight. The consequences of the research compare?two codes in term of weights and design performances.?This will aid professional engineers and researchers to select effective design criteria and capacity design rules?efficiently.

关键词： Eurocodes AISC ASCE FEMA Moment Resisting Frames Seismic Resistance Pushover Analysis

淮河鲁台子至淮南段防洪保护区洪水计算模型及风险分析

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淮河鲁台子至淮南段防洪保护区洪水计算模型及风险分析

作者： umar farooq 天津大学

学位级别：硕士

淮河受黄河长期夺淮影响,加之复杂的自然、经济和社会等条件,历次洪水具有洪量大、洪峰高、历时长的特点,流域洪水灾害严重。洪水演进数值模拟能够直观把握不同工况洪水演进情况及淹没水深、淹没范围等洪水风险要素,基于洪水演进数值模... 详细信息

淮河受黄河长期夺淮影响,加之复杂的自然、经济和社会等条件,历次洪水具有洪量大、洪峰高、历时长的特点,流域洪水灾害严重。洪水演进数值模拟能够直观把握不同工况洪水演进情况及淹没水深、淹没范围等洪水风险要素,基于洪水演进数值模拟开展洪水影响评估能够为防汛部门防灾减灾决策提供技术支持,制定科学的防洪调度方案和抗洪抢险预案。本文主要研究内容及结论如下:构建鲁台子至淮南段-茨南淝左片防洪保护区一、二维动态耦连洪水演进数值计算模型模拟河道-防洪保护区洪水演进过程。以淮河干流鲁台子水文站2003年和2007年洪水过程作为上边界条件,淮南水位站2003年和2007年洪水过程作为下边界条件,利用2003年、2007年峡山口水位站实测水位数据分别对河道一维水动力模型进行了率定与验证,结果表明所建淮河河道一维水动力模型能够很好满足淮河鲁台子至淮南段防洪保护区洪水风险分析的需要。采取干湿水深、地物概化多种措施对构建的防洪保护区二维洪水演进模型进行优化。对茨南淝左片防洪保护区遭遇淮河干流50年一遇、100年一遇设计洪水工况的进行洪水演进数值模拟和洪水淹没风险分析,比较和分析不同工况洪水演进情况及淹没水深、淹没范围等洪水风险要素。依据洪水演进数值模拟得到的茨南淝左片防洪保护区遭遇50年一遇、100年一遇设计洪水情况下的淹没范围、淹没水深等洪水风险要素,利用GIS和洪灾损失率,叠加分析淹没信息与社会经济指标分布图层,获得50年一遇和100年一遇洪水淹没区面积分别为794.29km和635.43km,整理受影响的村庄、耕地、道路和GDP信息等。分类统计不同计算方案对应的洪水影响结果,并对结果进行分析比较。研究结果对可对该防洪保护区洪水风险分析和损失评估提供技术支撑,对区域防洪减灾决策与建设规划具有重要参考价值。

关键词：洪水演进数值模拟风险分析防洪保护区淮

Hydroiodic Acid Additive Enhanced the Performance and Stability of PbS-QDs Solar Cells via Suppressing Hydroxyl Ligand

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纳微快报：英文版 2020年第3期12卷 117-128页

作者： Xiaokun Yang Ji Yang Jahangeer Khan Hui Deng Shengjie Yuan Jian Zhang Yong Xia Feng Deng Xue Zhou farooq umar Zhixin Jin Haisheng Song Chun Cheng Mohamed Sabry Jiang Tang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyLuoyu Road 1037Wuhan 430074People’s Republic of China Department of Materials Science and Engineering and Shenzhen Key Laboratory of Nanoimprint Technology South University of Science and TechnologyShenzhen 518055People’s Republic of China Shenzhen R&D Center of Huazhong University of Science and Technology Shenzhen 518000People’s Republic of China School of Optical and Electronic Information Huazhong University of Science and Technology1037 Luoyu RoadWuhan 430074People’s Republic of China National Center for Magnetic Resonance in Wuhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071People’s Republic of China Physics Department College of Applied ScienceUmm Al-Qura UniversityMeccaKingdom of Saudi Arabia Solar Physics Lab National Research Institute of Astronomy and GeophysicsCairoEgypt

The recent emerging progress of quantum dot ink(QD-ink)has overcome the complexity of multiple-step colloidal QD(CQD)film preparation and pronouncedly promoted the device ***,the detrimental hydroxyl(OH)ligands induced from synthesis procedure have not been completely ***,a halide ligand additive strategy was devised to optimize QD-ink *** simultaneously reduced sub-bandgap states and converted them into iodide-passivated surface,which increase carrier mobility of the QDs films and achieve thicker absorber with improved *** corresponding power conversion efficiency of this optimized device reached 10.78%.(The control device was 9.56%.)Therefore,this stratege can support as a candidate strategy to solve the QD original limitation caused by hydroxyl ligands,which is also compatible with other CQD-based optoelectronic devices.

关键词： Hydroxyl ligand HI additive Surface passivation Quantum dots ink Solar cells

Vegetative Development of <i>Sparassis crispa</i>in Various Growth Conditions and Effect of Electric Pulse Simulation on Its Fruit Body Production

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Advances in Microbiology 2014年第5期4卷 267-274页

作者： Muhammad umar farooq Alfred Chioza, Shoji Ohga Department of Agro-Environmental Sciences Faculty of Agriculture Kyushu University Fukuoka Japan

This study was carried out to detect the favorable mycelial growth conditions and effect of electric pulse stimulation on fruit body production of SC-1 strain of Sparassis crispa. The optimum growth in PDA was found at 25°C (67 mm colony diameter in 28 days) followed by 20°C (63 mm colony diameter in 28 days). There was no mycelial growth at 35°C. The most favourable initial media pH range was found to be 5 - 7 and colony diameter measurements were not statistically different among these pH values (p > 0.05). However, the highest growth was obtained at pH 6 (57 mm colony diameter in 28 days). A basal medium composed of 0.05 g MgSO4, 0.46 g KH2PO4, 1.0 g K2HPO4, 120 μg thiamine-HCl, 20 g agar and 1000 ml of distilled water was used to investigate growth response of S. crispato different carbon and nitrogen sources. In 28 days, fructose and glucose exhibited best growth (49.4 mm and 31.6 mm colony diameters respectively) and there was no growth on the basal medium supplemented with galactose. Basal medium supplemented with glycine and alanine as nitrogen sources resulted in best growth, 54.4 mm and 50.5 mm colony diameters respectively. There was no mycelial growth in culture medium supplemented with ammonium acetate, ammonium phosphate, arginine and histidine. Electric pulse stimulation improved the fruiting body production. The yields obtained from all bottles in which electric pulse was applied were significantly higher than the yields from the bottles in which electric pulse was not applied. The percent increases of fresh weight yield from control on 100, 120, 130, and 170 kilovolts were 36%, 44%, 75% and 81% respectively. As regard to dry weight yield, the percent increases from control on 100, 120, 130, and 170 kilovolts were 27%, 54%, 63% and 67% respectively.

关键词： Sparassis crispa Fruit Body Production Mycelial Growth Electric Pulse Stimulation

Three new anthraquinone derivatives isolated from Symplocos racemosa and their antibiofilm activity

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Chinese Journal of Natural Medicines 2017年第12期15卷 944-949页

作者： umar farooq Sara Khan Sadia Naz Ajmal Khan Afsar Khan Ayaz Ahmed Abdur Rauf Syed Majid Bukhari Shujaat Ali Khan Arfa Kamil Nadia Riaz Abdur Rahman Khan Department of Chemistry COMSATS Institute of Information Technology Abbottabad-22060 Pakistan Dr. Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological Sciences University of Karachi- 752 70 Pakistan Department of Geology University of Swabi Anbar-23430 KPK Pakistan Institute of Chemical Sciences University of Peshawar Peshawar 25120 Pakistan Department of Pharmaceutical Chemistry Faculty of Pharmacy Federal Urdu University of Arts Science and Technology Karachi Karachi 75300 Pakistan Department of Environmental Sciences COMSATS Institute of lnformation Technology Abbottabad-22060 Pakistan

Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C(Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses(UV, IR, Mass, ~1 H-and ^(13)C-NMR, and two-dimensional(2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·m L^(-1) against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae.

关键词： Symplocos racemosa Substituted anthraquinone Antibiofilm activity