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Chinese Physics B 2016年第12期25卷 474-480页

作者： h mahfoz Kotb mohamad m ahmad Department of Physics College of ScienceKing Faisal University Department of Physics Faculty of ScienceAssiut University

We report on the measurements of the electrical and dielectric properties of Na1/2La1/2Cu3Ti4O12 （NLCTO） ce- ramics prepared by high energy ball-milling and conventional sintering without any calcination steps. The x-ray powder diffraction analysis shows that pure perovskite-like CCTO phase is obtained after sintering at 1025 ℃-1075 ℃. higher sintering temperatures result in multi-phase ceramics due to thermal decomposition. Scanning electron microscope observations reveal that the grain size is in a range of - 3 μm-5 μm for these ceramics. Impedance spectroscopy measurements performed in a wide frequency range （1 hz-10 mhz） and at various temperatures （120 K-470 K） are used to study the dielectric and electrical properties of NLCTO ceramics. A good compromise between high ε′ （5.7 ×10^3 and 4.1 × 10^3 at 1.1 khz and 96 khz, respectively） and low tan δ （0.161 and 0.126 at 1.1 khz and 96 khz, respectively） is obtained for the ceramic sintered at 1050 ℃. The observed high dielectric constant behavior is explained in terms of the internal barrier layer capacitance effect.

关键词： ceramics sintering dielectric loss and relaxation electrical

hydrogen Production from Glucose by Layered Double Oxides Photocatalysis

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Advances in Chemical Engineering and Science 2025年第1期15卷 17-30页

作者： moraya Alqahtani mohammed Bahattab mohammed Alabdulsalam Issa Abaalkheel ahmad Almater King Abdulaziz City for Science and Technology Riyadh Saudi Arabia

hydrogen (h2) production from renewable biomass resources plays a significant role in solving the shortage of fossil energy;hence, there is an interest in investigating alternative, cleaner processes. This work intends to study the photocatalytic production of hydrogen from D-(+)-Glucose by using different groups of catalysts that have been prepared (m2+ = Zn, mg and Ni) m2+/Ti4+ Al3+-LDhs (layered double hydroxides). It is then loaded Pd on the catalyst, and the effect of the composite catalyst, layered double hydroxides, is measured. After calcining, the catalyst for the conversion of Layered Double hydroxides (LDhs) to Layered Double Oxides (LDOs) is used to produce hydrogen gas from glucose. Photocatalytic reforming of glucose-derived compounds is an efficient method for the production of hydrogen. The purpose is to study the effect of metal ions on layered double oxide (LDO) materials by loading Pd and investigate hydrogen production from glucose. The metal cations in the layer were distributed through the preparation of the catalyst process by ion and atom scale between the layers, which were dispersed systematically, as well as the controlled component catalysis. This process shows that ZnTiAl-LDO had the best effect as a catalyst in producing hydrogen compared to NiTiAl-LDO and mgTiAl-LDO.

关键词： Photocatalysis hydrogen Production Layered Double Oxides (LDO) D-(+)-Glucose

Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau

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Journal of Environmental Sciences 2025年第1期147卷 359-369页

作者： Xiaoqing han Pengfei Dang Lechen Liao Fangqi Song miaomiao Zhang maoxue Zhang Guoqing Li Shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles O.Joseph Kadambot h.m.Siddique College of Agronomy Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess PlateauNorthwest A&F UniversityYanglingShaanxi 712100China Department of Crop Sciences and Beekeeping Technology College of Agricultural Sciences and Food Technology University of Dar es SalaamMwalimu Julius Nyerere Mlimani CampusP.O.Box 35091Dar es SalaamTanzania College of Life Science Yulin UniversityChongwen Road No.4YulinShaanxi719000China The UWA Institute of Agriculture and School of Agriculture&Environment The University of Western AustraliaPerth WA 6001Australia

Agricultural practices significantly contribute to greenhouse gas(GhG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize *** film mulching is commonly used in the Loess Plateau *** slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop *** these techniques represents a novel agricultural approach in semi-arid ***,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research ***,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(Pm-U),and slow-release fertilizer supplied with plastic film mulching(Pm-S)]on soil fertility,economic and environmental *** results revealed that nitrogen fertilizer was the primary contributor to total GhG emissions(≥71.97%).Compared to other treatments,Pm-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,Pm-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,Pm-S increased SOCS(0-40 cm)by 2.46%,while Pm-U decreased it by 7.09%.These findings highlight the positive effects of Pm-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.

关键词： Plastic film mulching Slow-release fertilizer maize grain yield Carbon footprint Economic benefits

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis h.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Antimonene-based saturable absorber for a soliton mode-locked and Q-switched fiber laser in the 2 μm wavelength region

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Chinese Physics B 2023年第6期32卷 259-269页

作者： h ahmad B Nizamani m Z Samion N Yusoff m F Ismail Photonics Research Centre Universiti Malaya50603 Kuala LumpurMalaysia Physics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguished Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

We demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switched laser in the 2 μm wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium–holmiumdoped fiber laser to produce the pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in thin-film form for the generation of Q-switched pulses. The mode-locking was stable within a pump power of 267 m W–511 m W, and the laser operated at a central wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 mhz, with a signal-to-noise ratio of 64 d B. Q-switched laser operation was stable at a wavelength of 1890.1 nm within a pump power of 312 m W–381 m W. With the increase in pump power from 312 m W to 381 m W, the repetition rate increased to a maximum of 56.63 k hz and the pulse width decreased to a minimum value of 2.85 μs. Wide-range tunability of the Q-switched laser was also realized within the wavelength range of1882 nm–1936 nm.

关键词： mode-locking Q-switched fiber laser optical saturable absorber

Analgesia and Safety of Perioperative Bilateral Erector Spinae Infusion versus Thoracic Epidural Infusion in Upper Abdominal Oncological Surgeries: A Randomized Clinical Trial

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Open Journal of Anesthesiology 2025年第1期15卷 13-29页

作者： Amin mohamed Ashraf mohammad Abd El-Rahman ahmad hussein mahmoud mohamed mohammed Abdelemam Rania Department of Anesthesiology ICU and Pain Management South Egypt Cancer Institute Assiut University Assiut Egypt

Objective: Erector spinae plane block is a novel regional anaesthetic intervention that is said to have an effective analgesic profile in the upper abdominal region. We compared its analgesic efficacy with thoracic epidural block for upper abdominal cancer surgeries. methods: This prospective study included 60 patients, 18 to 65 years old with ASA class II who underwent gastrectomy and Whipple’s procedures under general anesthesia. Patients were assigned into two groups: Thoracic epidural group, with injection of 0.1 ml/kg of bupivacaine 0.25% in epidural catheter followed by 0.1 ml/kg/h of 0.125% bupivacaine infusion for 48 hrs., and Erector spinae group, with insertion of bilateral erector spinae catheters to inject 0.1 ml/kg of bupivacaine 0.25% followed by bilateral infusion of 0.1 ml/kg/h of bupivacaine 0.125% for 48 hrs. The primary endpoint was postoperative VAS scores at rest and movement. Secondary endpoint included postoperative total opioid consumption, 1st request for analgesia, hemodynamic changes and satisfaction scores. Results: Pain scores and needed rescue analgesia in both groups were comparable. however, 1st request for opioid was significantly longer in TEPI compared to ESI group. hemodynamics were significantly lower in TEPI group with no differences in the incidence of postoperative complications except for hypotension. Patient satisfaction scores were arbitrarily higher in ESI group without significance. Conclusion: Erector spinae infusion is a highly promising regional technique with comparable effects to thoracic epidural blockade in reducing pain and opioid needs while causing minimal hemodynamic consequences.

关键词： Erector Spinae Abdominal Cancer Surgeries Thoracic Epidural

Blood-based magnetohydrodynamic Casson hybrid nanofluid flow on convectively heated bi-directional porous stretching sheet with variable porosity and slip constraints

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Chinese Physics B 2025年第1期34卷 294-306页

作者： Showkat ahmad Lone Rawan Bossly Fuad S.Alduais Afrah Al-Bossly Arshad Khan Anwar Saeed Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic University(Jeddah-M)Riyadh-11673Saudi Arabia Department of ma.h.matics College of ScienceJazan UniversityJazan 82817Saudi Arabia Department of ma.h.matics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia College of Aeronautical Engineering National University of Sciences and TechnologySector H-12Islamabad 44000Pakistan Department of ma.h.matics Abdul Wali Khan UniversityMardan 23200KhyberPakhtunkhwaPakistan

Fluid flow through porous spaces with variable porosity has wide-range applications,notably in biomedical and thermal engineering,where it plays a vital role in comprehending blood flow dynamics within cardiovascular systems,heat transfer and thermal management systems improve efficiency using porous materials with variable *** these important applications in view,in current study blood-based hybrid nanofluid flow has considered on a convectively heated *** sheet exhibits the properties of a porous medium with variable porosity and extends in both the x and y *** has used as base fluid in which the nanoparticles of Cu and Cu O have been *** radiation,space-dependent,and thermal-dependent heat sources have been incorporated into the energy equation,while magnetic effects have been integrated into the momentum *** variables have employed to transform the modeled equations into dimensionless form and facilitating their solution using bvp4c *** has concluded in this study that,both the primary and secondary velocities augmented with upsurge in variable porous factor and declined with escalation in stretching ratio,Casson,magnetic,and slip factors along x-and *** distribution has grown up with upsurge in Casson factor,magnetic factor,thermal Biot number,and thermal/space-dependent heat sources while has retarded with growth in variable porous and stretching ratio *** findings of this investigation have been compared with the existing literature,revealing a strong agreement among present and established results that ensured the validation of the model and method used in this work.

关键词： hybrid nanofluid Casson fluid magnetohydrodynamics variable porous space space/thermaldependent heat sources velocity slip and thermal convective conditions

Optically modulated Tunable O-Band Praseodymium-Doped Fluoride Fiber Laser Utilizing multi-Walled Carbon Nanotube Saturable Absorber

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Chinese Physics Letters 2019年第10期36卷 32-35页

作者： h.ahmad m.F.Ismail S.N.Aidit Photonics Research Center University of MalayaKuala Lumpur 50603Malaysia Physics Department Faculty of ScienceUniversity of Malaya50603 Kuala LumpurMalaysia

A tunable and optically modulated fiber laser utilizing a multi-walled carbon nanotube based saturable absorber is demonstrated for operation in the O-band region.A praseodymium-doped fluoride fiber is used as the gain medium and the system is capable of generating modulated outputs at 1300 *** output is observed at pump powers of 511 mW and above,with repetition rates and pulse widths that can be tuned from 41 khz and 3.4μs to 48 khz and 2.4μs,respectively,at the maximum pump power available.A maximum average output power of 100μW with a corresponding single pulse energy of 2.1 nJ is measured,while the tunability of the proposed laser is from 1290 nm to 1308 *** output is stable,with peak power fluctuations of^4 dB from the average value.

关键词： pump fiber Optically

豫西九仗沟金矿床黄铁矿地球化学特征及其找矿意义

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地质力学学报 2025年第1期31卷 61-79页

作者：司建涛白德胜赵志强梁贞阳静楠刘建平丁涛 Osama ahmad 河南省第二地质矿产调查院有限公司河南郑州450001 有色金属成矿预测与地质环境监测教育部重点实验室(中南大学) 湖南长沙410083

黄铁矿是金矿床中重要的载金矿物,其地球化学特征不仅在矿床成因中具有重要的指示作用,也是重要的找矿信息。豫西九仗沟金矿床作为熊耳山金矿集区典型的构造蚀变岩型金矿床,是探讨黄铁矿对金矿床成因指示及找矿标志的理想矿床。通过开... 详细信息

黄铁矿是金矿床中重要的载金矿物,其地球化学特征不仅在矿床成因中具有重要的指示作用,也是重要的找矿信息。豫西九仗沟金矿床作为熊耳山金矿集区典型的构造蚀变岩型金矿床,是探讨黄铁矿对金矿床成因指示及找矿标志的理想矿床。通过开展九仗沟金矿床构造蚀变带调查,采集+260 m至-20 m垂深280 m的构造蚀变岩样品8件,对蚀变岩中黄铁矿进行矿物电子探针及激光剥蚀等离子体质谱分析,探讨不同蚀变带黄铁矿的元素含量特征及变化规律,以期获得黄铁矿对矿床成因及深部找矿的指示意义。研究结果表明,九仗沟金矿床+260 m中段至-20 m中段区间可划分为4个蚀变带,蚀变岩中黄铁矿均为成矿期黄铁矿,黄铁矿Fe、S元素含量显示其主要为硫亏型;微量元素聚类分析显示;Au与Cu、As、Sb、Zn、Ag、Te、Se、Pb为一组,属于中—低温元素组合;Co/Ni比值为1~10,Co-Ni-As图解显示黄铁矿为岩浆热液成因;黄铁矿中Au与Cu、As、Sb、Zn、Ag、Te、Pb呈正相关性,在第1—3蚀变带其含量同步逐渐降低,而在第4蚀变带则出现跳跃上升,第4蚀变带与第1—3蚀变带为不同期次热液成矿活动的产物。根据第1—3蚀变带的垂向延伸情况,推测第4蚀变带延深可达-60 m标高,深部至少还可以勘探一个中段(40 m),具有良好的找矿前景。黄铁矿中Au、Cu、As、Sb、Zn、Ag、Te、Se和Pb等元素含量及Au/As、Au/Ag、Co/Ni比值对垂向蚀变分带具有重要的指示作用,黄铁矿的微量元素标志是金矿床深部找矿靶区的重要信息。

关键词：黄铁矿微量元素找矿预测九仗沟金矿床豫西

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Precipitation Study in Inconel 625 Alloy by Positron Annihilation Spectroscopy

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Journal of materials Science & Technology 2003年第5期19卷 434-436页

作者： m.ahmad. W.ahmad. m.A.Shaikh mahmud ahmad m.U.Rajput Nuclear Physics Division Pakistan Institute of Nuclear Science & Technology P.O. Nilore Islamabad PakistanNuclear Physics Division Pakistan Institute of Nuclear Science & Technology P.O. Nilore Islamabad PakistanNuclear Physics Division Pakistan Institute of Nuclear Science & Technology P.O. Nilore Islamabad PakistanNuclear Physics Division Pakistan Institute of Nuclear Science & Technology P.O. Nilore Islamabad Pakistan Nuclear Physics Division Pakistan Institute of Nuclear Science & Technology P.O. Nilore Islamabad Pakistan

Precipitation in Inconel 625 alloy has been studied by positron annihilation spectroscopy and electron microscopy. The observed dependence of annihilation characteristics on aging time is attributed to the change of the positron state due to the increase and decrease of the density and size of the 7' precipitates. hardness measurements and lifetime measurements are in good agreement.

关键词： Positron lifetime Precipitation Inconel 625 alloy Fast-fast coincidence system hardness