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Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

Hydromagnetic oscillatory Couette flow in rotating system with induced magnetic field

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Applied mathematics and mechanics(English Edition) 2014年第10期35卷 1331-1344页

作者： G.s.sETH s.m.HUssAIN s.sARKAR Department of Applied mathematics Indian School of Mines Department of mathematics O.P.Jindal Institute of Technology

This paper presents a study of hydromagnetic Couette flow of an incompress- ible and electrically conducting fluid between two parallel rotating plates, one of which is oscillating in its own plane. A uniform transverse magnetic field is used, and the induced magnetic field is taken into account. The exact solution to the governing equations is obtained in a closed form. The solution to the problem in the case of vanishing and small finite magnetic Prandtl numbers is also derived from the general solution. The asymp- totic behavior of the solution for large values of the frequency parameter is analyzed to gain some physical insights into the flow pattern. Expressions for the shear stress at both the oscillatory and stationary plates due to primary and secondary flows and mass flow rate in the primary and secondary flow directions are also obtained. The results of the fluid velocity and the induced magnetic field are presented. The shear stresses on the plates due to the primary and secondary flows and the corresponding mass flow rates are presented in a tabular form.

关键词： magnetic interaction parameter Ekman number frequency parameter,hydromagnetic stokes-Ekman boundary layer magnetic diffusion boundary layer

Targeting DNA repair pathways to overcome cancer drug resistance

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Cancer Drug Resistance 2021年第4期4卷 837-841页

作者： Robert C.A.m.van Waardenburg Eddy s.yang Department of Pharmacology and Toxicology University of Alabama at BirminghamBirminghamAL 35233USA Department of Radiation Oncology University of Alabama at BirminghamBirminghamAL 35233USA O’Neal Comprehensive Cancer Center University of Alabama at BirminghamBirminghamAL 35233USA

DNA damage response and DNA repair pathways are evolutionarily conserved from prokaryotes to eukaryotes to protect the host from genomic *** of proteins involved in these pathways in mammalian cells increases genomic alterations leading to genomic instability,a well-established hallmark of cancer^([1,2]).However,our understanding of the signaling pathways to repair DNA damage in cancers has grown exponentially over the last decades.

关键词： damage alterations cancer

The Electronic structures of Dimeric Diboroxane and Aldiminoborane

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Chemical Research in Chinese Universities 1995年第3期11卷 232-237页

作者： WANG, ZZ XU, m yang, ZZ JILIN UNIV INST THEORET CHEMCHANGCHUN 130023PEOPLES R CHINA JILIN UNIV NATL LAB THEORET & COMPUTAT CHEMCHANGCHUN 130023PEOPLES R CHINA

e have studied the electronic structures of dimeric diboroxane and aldiminob-orane by nieans of sTO-3G .ib iuitio sCF method. The energies and the componentanalysis of niolecular orbitals near to frontier orbital have been given. By bothKoopman' s theoreni and △E_(scf)mietliod we have calculated the ionization potentialsof 8 higlier occupied orbitals and discussed the electron relaxation effect on IP' s cal-culations and the charge distribuuons for the two molecules.

关键词： Diboroxane Aldiniuioborane ab initio sCF method

Cost-effective integrated strategy for the fabrication of hard-magnet barium hexaferrite powders from low-grade barite ore

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International Journal of minerals,metallurgy and materials 2016年第9期23卷 991-1000页

作者： m.m.s.sanad m.m.Rashad Central metallurgical R & D Institute

Ultrafine barium hexaferrite（BaFe12O19） powders were synthesized from the metallurgical extracts of low-grade Egyptian barite ore via a co-precipitation route. Hydrometallurgical treatment of barite ore was systematically studied to achieve the maximum dissolution efficiency of Fe（～99.7%） under the optimum conditions. The hexaferrite precursors were obtained by the co-precipitation of Bas produced by the reduction of barite ore with carbon at 1273 K and then dissolved in diluted HCl and FeCl3 solution at pH 10 using NaOH as a base; the product was then annealed at 1273 K in an open atmosphere. The effect of Fe^3＋/Ba^2＋ molar ratio and the addition of hydrogen peroxide（H2O2） on the phase structure, crystallite size, morphology, and magnetic properties were investigated by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. single-phase BaFe（12）O（19） powder was obtained at an Fe^3＋/Ba^2＋ molar ratio of 8.00. The formed powders exhibited a hexagonal platelet-like structure. Good maximum magnetization（48.3 A×m^2×kg^–1） was achieved in the material prepared at an Fe^3＋/Ba^2＋ molar ratio of 8.0 in the presence of 5% H2O2 as an oxidizer and at 1273 K because of the formation of a uniform, hexagonal-shaped structure.

关键词： chemical process barite ore treatment characterization magnetic properties ferrites

Irrigating with cooler water does not reverse high temperature impact on grain yield and quality in hybrid rice

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The Crop Journal 2023年第3期11卷 904-913页

作者： Wanju shi Xinzhen Zhang Juan yang somayanda m.Impa De Wang Yusha Lai Zijin yang Hang Xu Jinshui Wu Jianhua Zhang s.V.Krishna Jagadish College of Agronomy Hunan Agricultural UniversityChangsha 410128HunanChina Department of Biology Hong Kong Baptist UniversityKowloonHong KongChina state Key Laboratory of Agrobiotechnology The Chinese University of Hong KongShatinHong KongChina Department of Plant and soil sciences Texas Tech UniversityLubbockTX 79410USA International Rice Research Institute DAPO Box 7777Metro ManilaPhilippines

Rice grain yield and quality are negatively impacted by high temperature *** water temperature significantly affects rice growth and development,thus influencing yield and *** role of cooler irrigation water in counteracting high temperature induced damages in rice grain yield and quality are not ***,in the present study two rice hybrids,Liangyoupeijiu(LYPJ)and IIyou 602(IIY602)were exposed to heat stress and irrigated with water having different temperatures in a splitsplit plot experimental *** stress was imposed starting from heading until maturity under field-based heat tents,over two consecutive *** maximum day temperature inside the heat tents was set at 38℃.For the irrigation treatments,two different water sources were used including belowground water with cooler water temperature and pond water with relatively higher water *** mean temperatures in the heat tents were increased by 1.2–2.0℃ across two years,while nighttime temperature remained similar at both within and outside the heat *** belowground water irrigation did have little effect on air temperature at the canopy level but decreased soil temperature(0.2–1.4℃)especially under *** stress significantly reduced grain yield(33%to 43%),panicles m^(-2)(9%to 10%),spikelets m^(-2)(15%to 22%),grain-filling percentage(13%to 26%)and 1000-grain weight(3%to 5%).Heat stress significantly increased chalkiness and protein content and decreased grain length and amylose *** yield was negatively related to air temperature at the canopy level and soil *** grain quality parameters like chalkiness recorded a significantly positive association with both air and soil *** with cooler belowground water reduced the negative effect of heat stress on grain yield by 8.8%in LYPJ,while the same effect was not seen in IIY602,indicating cultivar differences in their response to irrigation water ***

关键词： Grain quality Grain yield Hybrid rice High temperature Irrigation Water management

Roles of dietary taurine in fish nutrition

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marine Life science & Technology 2020年第4期2卷 360-375页

作者： W.W.H.A.sampath R.m.D.s.Rathnayake mengxi yang Wenbing Zhang Kangsen mai The Key Laboratory of Aquaculture Nutrition and Feeds Ministry of Agriculture and Rural AffairsQingdao 266003China The Key Laboratory of mariculture Ministry of EducationQingdao 266003China Ocean University of China Qingdao 266003.China Developmental molecular Biology Laboratory Ocean University of ChinaQingdao 266003China Laboratory for marine Fisheries science and Food Production Process Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Taurine is a conditionally essential amino acid in fish *** present study addressed the practical application of examining published data on fish nutrition over the past 20 years,emphasizing the topic of taurine by using computational tools and their *** to the published articles,an increased linear growth of research occurred,with Japanese flounder being the most examined fish *** taurine supplementation has several beneficial effects in fish nutrition,such as survival,growth,feed utilization,protein and energy retention,intermediate metabolism,anti-oxidation,anti-stress,disease resistance,muscle texture and reproductive ***,there are negative effects in some *** taurine exerted effects on several gene expressions and enzyme activities;these are important in taurine metabolism in *** genes and enzymes included taurine transporter(TauT),cysteine dioxygenase(CDO),cysteamine dioxygenase(ADO),cysteine sulfonate decarboxylase(CsD)and pretrypsinogen(Ptry).Plant protein-based diets with taurine supplementation are recommended because of the absence of taurine in plani protein.

关键词： Taurine Fish Amino acid Nutrition Feed

Catalytic effect of srTiO_3 on the hydrogen storage behaviour of mgH_2

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Journal of Energy Chemistry 2019年第1期28卷 46-53页

作者： m.s.Yahya m.Ismail school of Ocean Engineering University Malaysia Terengganu

The effects of sr TiO_3 on the hydrogen storage properties of mgH_2 have been studied for the first *** onset dehydrogenation temperature of the mgH_2-10 wt% srTiO_3 is found to be 275 ℃, which is 55 ℃ lower as compared to the as-milled mgH_2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled mg H_2. meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled mg H_2 at 320 ℃. The calculated Eaof the mg H_2-10 wt% srTiO_3 is 109 k J/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled mgH_2. The sr TiO_3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the srTiO_3 is owing to its ability to change the physical structure of the mgH_2 particles during the ball milling process.

关键词： Hydrogen storage magnesium hydride Catalytic effect sorption properties

Effects of Zr substitution on structural,morphological,and magnetic properties of bismuth iron oxide phases

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Chinese Physics B 2017年第8期26卷 450-455页

作者： A Asif m Hassan s Riaz s Naseem s s Hussain materials Growth and simulation Laboratory Department of PhysicsUniversity of the PunjabLahore-54590Pakistan Center of Excellence in solid state Physics University of the PunjabLahore-54590Pakistan

The present study involves co-precipitation method to grow un-doped and Zr-doped bismuth iron oxide with x_（Zr）=0.10–0.30. The molar solutions of ferric chloride（FeCl_3）, zirconyle chloride（ZrOCl_2）, and bismuth chloride（BiCl_3） are prepared in distilled water, and are allowed to react with sodium hydroxide（Na OH）. The synthesized powders are then converted into pellets, which are sintered at 500℃ for two hours in a muffle furnace. X-ray diffraction（XRD） shows multi-phase formation in un-doped and Zr doped samples. scanning electron microscope（sEm） depicts layered structure at low Zr concentration x_（Zr）= 0.10, while uniform surface with smaller grains and voids is observed at x_（Zr）= 0.20, but at x_（Zr）= 0.30, cracks and voids become prominent. The ferromagnetic nature of the un-doped sample is observed by vibrating sample magnetometer（Vsm）, while paramagnetic behavior appears due to Zr doping. The ferromagnetism in un-doped sample is lost by Zr doping, which is due to the formation of additional Fe–O–Zr bonds that induce paramagnetic behavior.

关键词： co-precipitation multi-phases ferromagnetism paramagnetism BiFeO3