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Pyrrolidine dithiocarbamate reduces ischemia-reperfusion injury of the small intestine

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World Journal of Gastroenterology 2005年第46期11卷 7308-7313页

作者： ismail h mallick Wen-Xuan Yang Marc C Winslet Alexander M Seifalian GI and hepatobiliary Research Unit University Department of Surgery Royal Free and University College Medical School University College London LondonUnited Kingdom Department of Surgery Royal Free Hospital Hampstead NHS Trust London United Kingdom

AIM： To evaluate whether pyrrolidine dithiocarbamate （PDTC）, an enhancer of hO production, attenuates intestinal IR injury. METhODS： Eighteen male rats were randomly allocated into three groups：（a） sham; （b） IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and （c） PDTC treatment before IR. Intestinal microvascular perfusion （IMP） was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase （LDh） levels and biopsies of ileum were obtained. hO activity in the ileum was assessed at the end of the reperfusion period. RESULTS： At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline （P〈0.05 vs sham）, whereas PDTC improved IMP to 67.3% of baseline （P〈0.01 vs IR）. There was a twofold increase in hO activity in PDTC group （2 062.66±106.11） as compared to IR （842.3±85.12）（P〈0.001）. LDh was significantly reduced （P〈0.001） in PDTC group （585.6±102.4） as compared to IR group （1 973.8±306.5）. histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION： Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via hO production. Additional studies are warranted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.

关键词： Intestine Ischemia-reperfusion injury heme oxygenase Pyrrolidine

Controversies in the treatment of common anal problems

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World Journal of Gastroenterology 2006年第20期12卷 3146-3154页

作者： ismail Sagap Feza h Remzi Department of Colorectal Surgery(A-30) Cleveland Clinic Foundation 9500 Euclid AvenueClevelandOH 44195United States

Treating common benign anal diseases has evolved towards more outpatient procedures with better outcome. however, minimizing post-procedure morbidities such as pain and the avoidance incontinence remain the most significant concerns. We introduce some controversies and highlight the developments in current surgical practice for the treatment of common anal problems.

关键词： Anal problems Treatment

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

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

Corrosion Penetration and Crystal Structure of AA5022 in hCl Solution and Rare Earth Elements

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Journal of Materials Science & Technology 2005年第3期21卷 324-330页

作者： A.A.El-Meligi S.h.Sanad A.A.ismail A.M.Barakat Electrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypElectrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypElectrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypChemistry Dept. Faculty of Science Cairo University Cairo Egypt

Al-alloy (AA5022) corrosion penetration (CP) and crystal structure were investigated after running static immersion corrosion tests in 1 mol/L hCl solution and different concentrations of rare earth elements (La3+), (Ce3+) and their combination, at different temperatures. X-ray diffraction (XRD) was used to examine the surface structure before and after immersion, and secondary electron detector (SED) was operated to study surface morphology. In 1 mol/L hCI solution the corrosion penetration increased with increasing temperature and immersion time. The increase of La3+ concentrations up to 1000×10-6 g/L led to the decrease in the corrosion penetration, and the decrease in Ce3+ concentrations up to 50×10-6 g/L decreases the corrosion penetration of the alloy. Mix3 (combination of La3+ and Ce3+) dramatically reduced the corrosion penetration. This suggests that a synergistic effect exists between La3+ and Ce3+. The reaction kinetics both in absence and presence of La3+ and Ce3+ and their combination would follow a parabolic rate law. The XRD patterns revealed that the intensities of certain hkl phases are affected. The crystalline structure has not been deformed either before or after testing and there are no additional peaks except that of the as-received alloy. In the case of accelerating CP, the surface morphology shows that the roughness and voids of surface are increased.

关键词： Al-alloy Corrosion penetration Crystal structure XRD

Conversion of Malaysian low-rank coal to mesoporous activated carbon:Structure characterization and adsorption properties

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1716-1727页

作者： Ali h.Jawad Khudzir ismail Mohd Azlan Mohd Ishak Lee D. Wilson Faculty of Applied Sciences Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia Faculty of Applied Sciences Universiti Teknologi MARA02600 ArauPerlisMalaysia Department of Chemistry University of SaskatchewanSaskatoonSaskatchewan S7N 5C9Canada

Malaysian Selantik low-rank coal(SC)was used as a precursor to prepare a form of mesoporous activated carbon(SC-AC)with greater surface area(SA)via a microwave induced KOh-activation *** characteristics of the SC and SC-AC were evaluated by the iodine number,ash content,bulk density,and moisture content The structure and surface characterization was carried out using pore structure analysis(BET),scanning electron microscopy with energy dispersive X-ray spectroscopy(SEM-EDX),X-ray diffraction(XRD),Fourier Transform Infrared(FTIR),elemental analysis(ChNS),thermogravimetric analysis(TGA),and determination of the point of zero charge(ph(PZC)).These results signify a mesoporous structure of SC-AC with an increase of ca.1160 times(BET SA=1094.3 m^2·g^-1)as compared with raw SC without activation(BET SA=1.23 m^2·g^-1).The adsorptive properties of the SC-AC with methylene blue(MB)was carried out at variable adsorbent dose(0.2-1.6 g·L^-1),solution ph(2-12),initial MB concentrations(25-400 mg·L^-1),and contact time(0-290 min)using batch mode *** kinetic profiles follow pseudo-second order kinetics and the equilibrium uptake of MB conforms to the Langmuir model with a maximum monolayer adsorption capacity of 491.7 mg g^-1 at 303 *** functions revealed a spontaneous endothermic adsorption *** mechanism of adsorption included mainly electrostatic attractions,hydrogen bonding interaction,andπ-πstacking *** work shows that Malaysian Selantik low-rank coal is a promising precursor for the production of low-cost and efficient mesoporous activated carbon with substantive surface area.

关键词： Coal Activated carbon Mesoporous material KOh activation Microwave irradiation Methylene blue

hydrochemical characterization of groundwater in Balad district, Salah Al-Din Governorate, Iraq

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Journal of Groundwater Science and Engineering 2018年第4期6卷 306-322页

作者： Alhassan h ismail Muntasir A Shareef Wesam Mahmood Middle Technical University Institute of Technology-Baghdad Water Resources Techniques Department

The assessment of hydrochemical quality of groundwater is very important to explore its nature and usefulness. In this paper, groundwater quality evaluation is carried out in the Balad district, Salah Al-Din Governorate, Iraq. A total of 28 groundwater samples are collected from shallow tube wells and analyzed for various physicochemical parameters. Groundwater suitability for drinking is evaluated based on the World health Organization(WhO) and Iraqi standards, and suitability of groundwater for irrigation is assessed based on various hydrochemical parameters. The results reveal that the dominant types of groundwater based on piper diagram are mixed CaMgCl and CaCl. Gibbs ratio indicates that the groundwater in the studied area is affected by the evaporation process. The cation-anion exchange reaction in the studied area demonstrates that 54% of the groundwater samples indicate a direct base(cation-anion) exchange reaction, while 46% of the groundwater samples indicating the chloro-alkaline disequilibrium. Furthermore, generally all of the groundwater samples are unsuitable for drinking and irrigation. Cluster analysis reveals two different groups of similarities between the groundwater samples, reflecting different pollution levels in the studied area.

关键词： Balad district Groundwater chemistry Water quality Cluster analysis GIS

Advanced hydrogen storage of the Mg–Na–Al system:A review

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Journal of Magnesium and Alloys 2021年第4期9卷 1111-1123页

作者： N.A.Ali M.ismail Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia

A solid-state storage system is the most practical option for hydrogen because it is more convenient and *** hydrides,especially Mgh_(2),are the most promising materials that offer high gravimetric capacity and good ***,the practical application of Mgh_(2) is restricted by slow sorption kinetics and high stability of thermodynamic *** storage performance of Mgh_(2) was enhanced by introducing the Mg–Na–Al system that destabilises Mgh_(2) with NaAlh_(4).The Mg–Na–Al system has superior performance compared to that of unary Mgh_(2) and NaAlh_(4).To boost the performance of the Mg–Na–Al system,the ball milling method and the addition of a catalyst were *** Mg–Na–Al system resulted in a low onset decomposition temperature,superior cyclability and enhanced kinetics *** Al_(12)Mg_(17) and NaMgh_(3) that formed in situ during the dehydrogenation process modify the reaction pathway of the Mg–Na–Al system and alter the thermodynamic *** this paper,the overview of the recent progress in hydrogen storage of the Mg–Na–Al system is *** remaining challenges and future development of Mg–Na–Al system are also *** paper is the first review report on hydrogen storage properties of the Mg–Na–Al system.

关键词： Mg-Na-Al system Mgh_(2) NaAlh_(4) Al_(12)Mg_(17) hydrogen storage

Crystallization Conditions and Petrogenesis of the Paleoproterozoic Basement Rocks in Bangladesh:An Evaluation of Biotite and Coexisting Amphibole Mineral Chemistry

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Journal of Earth Science 2014年第1期25卷 87-97页

作者： ismail hossain Toshiaki Tsunogae Department of Geology and Mining University of Rajshahi Faculty of Life and Environmental Sciences (Earth Evolution Sciences) University of Tsukuba Department of Geology University of JohannesburgAuckland Park 2006

The Paleoproterozoic （-1.73 Ga） basement rocks from Maddhapara, Bangladesh show a large range of chemical variations including diorite, quartz diorite, monzodiorite, quartz monzonite and granite. These are composed of varying proportions of quartz＋plagioclase＋K-feldspar＋biotite＋ hornblende±epidote＋titanite＋magnetite＋apatite and zircon. Amphibole and biotite, dominant ferro- magnesian minerals, have been analyzed with an electron microprobe. The biotite, Mg-dominant trioc- tahedral micas, is classified as phlogopitic nature. Relatively high Mg （1.33-1.53 pfu）, Mg^# （0.52-0.59） and low AIw （0.13-0.25 pfu） contents in the biotite reflect slightly fractionated magma, which might be a relative indicator for the origin of the parental magma. Biotite is also a very good sensor of oxidation state of the parental magma. Oxygen fugacity of the studied biotites estimate within the QFM and hM buffers and equilibrate at about -12.35 and -12.46, which exhibit the source materials were relatively higher oxidation state during crystallization and related to arc magmatism. Whereas, calcic amphi- boles, a parental member of arc-related igneous suite, display consistent oxygen fugacity values （-11.7 to -12.3）, low Al^# （0.16-0.21） with h2Omelt （5.6 wt.%-9.5 wt.%） suggest their reliability with the typical values of calc-alkaline magma crystallization. The oxygen fugacity of magma is related to its source material, which in turn depends on tectonic setting. Discrimination diagrams and chemical indices of both biotite and amphibole of dioritic rocks reveal calc-alkaline orogenic complexes; mostly I-type suite formed within subduction-related environments. Moreover, igneous micas are used as metal- logenic indicator. The biotites with coexisting amphibole compositions show an apparent calc-alkaline trend of differentiation. The study suggests that the trend of oxidized magmas is commonly associated with compressive tectonic and convergent plate boundaries.

关键词： oxygen fugacity biotite Paleoproterozoic basement rock Columbia supercontinent Bangladesh.