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Biomineralization of Uranium: A Simulated Experiment and Its Significance

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Acta Geologica Sinica(English Edition) 2005年第1期79卷 134-138页

作者： MINMaozhong huifangXU L.L.BARTON WANGJinping PENGXinjian h.WIATROWSKI DepartmentofEarthSciences StateKey.LaboratoryofMineralDepositResearchNanjingUniversityNanjingJiangsu210093China DepartmentofEarthandPlanetarySciences UniversityofNewMexicoAlbuquerqueNM87131-1116USA DepartmentofBiology UniversityofNewMexicoAlbuquerqueNM87131-1116USA

A simulated experimental reduction of and the synthesis of uraninite by a sulfate-reducing bacteria, Desulfovibrio desulfuricans DSM 642, are first reported. The simulated physicochemical experimental conditions were: 35°C, ph=7.0-7.4, corresponding to the environments of formation of the sandstone-hosted interlayer oxidation-zone type uranium deposits in Xinjiang, NW China. Uraninite was formed on the surface of the host bacteria after a one-week's incubation. Therefore, sulfate-reducing bacteria, which existed extensively in Jurassic sandstone-producing environments, might have participated in the biomineralization of this uranium deposit. There is an important difference in the order- disorder of the crystalline structure between the uraninite produced by Desulfovibrio desulfuricans and naturally occurring uraninite. Long time and slow precipitation and growth of uraninite in the geological environment might have resulted in larger uraninite crystals, with uraninite nanocrystals arranged in order, whereas the experimentally produced uraninite is composed of unordered uraninite nanocrystals which, in contrast, result from the short time span of formation and rapid precipitation and growth of uraninite. The discovery has important implications for understanding genetic significance in mineralogy, and also indicates that in-situ bioremediation of U-contaminated environments and use of biotechnology in the treatment of radioactive liquid waste is being contemplated.

关键词： microbial biomineralization uraninite sulfate-reducing bacteria sandstone-hosted uranium deposit simulated experiment

Chebyshev Collocation for Optimal Control in a Thermoconvective Flow

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Communications in Computational Physics 2009年第2期5卷 649-666页

作者： M.C.Navarro h.herrero S.hoyas Departamento de Matematicas Facultad de Ciencias QuımicasUniversidad de Castilla-La Mancha13071 Ciudad RealSpain Departamento de Informatica Escuela de IngenierıaUniversidad de Valencia46100 BurjassotValenciaSpain

In this paper a Chebyshev collocation method is used for solving numerically an optimal boundary control problem in a thermoconvective fluid *** aim of this study is to demonstrate the capabilities of these numerical techniques for handling this kind of *** the problem is treated in the primitive variable formulation additional boundary conditions for the pressure and the auxiliary pressure fields are required to avoid spurious modes.A dependence of the convergence of the method on the penalizing parameter that appears in the functional cost is *** this parameter approa.h.s zero some singular behaviour in the control function is observed and the order of the method *** singularities are irrelevant in the problem as a regularized control function produces the same results.

关键词： Chebyshev collocation optimal boundary control Boussinesq-Navier-Stokes

An Immersed Boundary-Lattice Boltzmann Prediction for Particle hydrodynamic Focusing in Annular Microchannels

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Chinese Physics Letters 2018年第10期35卷 89-92页

作者： Tao h Meng-Dan hU Si-si Zhou Dong-Ke SUN School of Mechanical Engineering Southeast UniversityNanjing 211189 School of Materials Science and Engineering Southeast UniversityNanjing 211189 School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189

We numerically study the dynamics of particle crystals in annular microchannels by the immersed-boundary（IB）lattice Boltzmann（LB） coupled model, analyze the fluid-particle interactions during the migration of particles,and reveal the underlying mechanism of a particle focusing on the presence of fluid flows. The results show that the Reynolds and Dean numbers are key factors influencing the hydrodynamics of particles. The particles migrate onto their equilibrium tracks by adjusting the Reynolds and Dean numbers. Elliptical tracks of particles during hydrodynamic focusing can be predicted by the IB-LB model. Both the small Dean number and the small particle can lead to a small size of the focusing track. This work would possibly facilitate the utilization of annular microchannel flows to obtain microfluidic flowing crystals for advanced applications in biomedicine and materials synthesis.

关键词： An Immersed Boundary-Lattice Boltzmann Prediction for Particle hydrodynamic Focusing in Annular Microchannels

Raman紫外双共振研究C_2h_2分子的碰撞转动弛豫

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物理学报 1992年第3期41卷 400-407页

作者：高文斌 R.DOPhEIDE h.Za.h.RIAS 杭州电子工业学院杭州310017 Fakult fr Physik Universit BielefeldFRG Fa.h.ereich Physik Universit/GHS EssenFRG

本文利用受激Raman抽运,选择性地制备了C_2h_2分子电子基态的红外非激活振动能级的单一转动态(X^1∑^+,v″=1,J″=9,11,13),并从紫外激光诱导的A^1Au(v′=1)←X^1∑^+(v″=1)荧光谱,直接测定上述三个转动态的C_2h_2—C_2h_2碰撞的消激... 详细信息

本文利用受激Raman抽运,选择性地制备了C_2h_2分子电子基态的红外非激活振动能级的单一转动态(X^1∑^+,v″=1,J″=9,11,13),并从紫外激光诱导的A^1Au(v′=1)←X^1∑^+(v″=1)荧光谱,直接测定上述三个转动态的C_2h_2—C_2h_2碰撞的消激活速率常数,它们分别为(7.96±1.04)×10^(-10),(8.79±0.97)×10^(-10),(8.76±0.88)×10^(-10)cm^3^(-1),以及由这些初始转动态向其它不同转动态(v′=1,J′=1,3,5,7,9,11,13,15)多量子跃迁转移的激活速率常数。

关键词：分子碰撞碳氢化合物转动驰豫

Liver involvement in the drug reaction,eosinophilia,and systemic symptoms syndrome

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World Journal of Clinical Cases 2019年第6期7卷 705-716页

作者： Sylvia A Martinez-Cabriales Neil h Shear Emmanuel I Gonzalez-Moreno Department of Medicine Division of DermatologySunnybrook Health Sciences CentreUniversity of Toronto Internal Medicine Department Dermatology DivisionHospital Universitario "Dr. José Eleuterio González"Universidad Autónoma de Nuevo León Department of Medicine Division of GastroenterologyUniversity of Calgary Internal Medicine Department Gastroenterology DivisionHospital Universitario "Dr. José Eleuterio González"Universidad Autónoma de Nuevo León

First described in 1996,the drug reaction,eosinophilia,and systemic symptoms syndrome(DReSS) is considered,along with Stevens-Johnson syndrome and toxic epidermal necrolysis,a severe cutaneous drug reaction. It is characterized by the presence of a maculopapular erythematous skin eruption,fever,lymphadenopa.h.,influenza-like symptoms,eosinophilia,and visceral involvement such as hepatitis,pneumonitis,myocarditis,pericarditis,nephritis,and colitis. The prognosis of patients with DReSS is related to the severity of visceral involvement. The mortality ranges from approximately 5% to 10%,and dea.h.is mainly due to liver failure,which is also the organ most commonly involved in this syndrome. Although it was previously hypothesized in 1994,DReSS syndrome can lead to reactivation of one or more human herpesvirus family members. Now being included as diagnostic criteria in a proposed diagnostic score system,this reactivation can be detected up to 2-3 wk after DReSS syndrome onset. Other causes of mortality in DReSS syndrome include myocardial or pulmonary lesions and hemophagocytosis. We reviewed the literature of previously reported case-series of DReSS and liver involvement,highlighting the pattern of liver damage,the treatment used,and the outcome.

关键词： Drug reaction,eosinophilia,and systemic symptoms syndrome Severe cutaneous drug reactions Drug-induced hypersensitivity syndrome Drug-induced liver injury Acute liver failure

Validity and reliability of the Dutch version of the displaced aggression questionnaire

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World Journal of Psychiatry 2021年第12期11卷 1288-1300页

作者： Danique Smeijers Thomas F Denson Erik h Bulten Inti A Brazil Behavioural Science Institute Radboud UniversityNijmegen 6525 HRThe Netherlands Pompestichting Nijmegen 6532 CNThe Netherlands School of Psychology University of New South WalesSydney 2052Australia Radboud University Donders Institute for Brain Cognition and BehaviourNijmegen 6525 GDThe Netherlands

BACKGROUND Displaced aggression occurs when a person encounters a provoking situation,is unable or unwilling to retaliate against the original provocateur,and subsequently aggresses against a target that is not the source of the initial *** displaced aggression questionnaire(DAQ)was developed to measure individual differences in the tendency to displace *** To develop a Dutch version of the DAQ and examine relationships between the DAQ and novel individual *** The Dutch version of the DAQ was created using a back-translation *** students(n=413)participated in the current *** questionnaires were administered *** The results confirmed the original three-factor structure and showed good reliability and *** also found differential relationships between trait displaced aggression,social anxiety and cognitive *** The results may indicate that distinct patterns exist in the development of the different dimensions of trait displaced *** study adds to the growing cross-cultural literature showing the robustness of trait displaced aggression in several different cultures.

关键词： Displaced aggression questionnaire Displaced aggression Questionnaire Dutch translation Psychometric properties

Wea.h.r Yield Model for the Semi Tropical Region (Pakistan)

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Advances in Atmospheric Sciences 1992年第3期9卷 367-372页

作者： Syed Faizan haider K.h.Asif Amjad hussain Gilani The Department of Agricultural Meteorology Uni. of Agricuture Faisalabad PakistanThe Department of Agricultural Meteorology Uni. of Agricuture Faisalabad PakistanDegree College Rawala Kot Azad Kashmir

Wea.h.r models are essential tools for checking of the effect of the wea.h.r elements in terms of their effect on the production of the crop. This research is an attempt to see the effect of only two variables i.e., temperature and rainfall for the division Faisalabad (semitropical region of Pakistan).The model fitted is of the linear form:the values of a,b, c have been found. The expected yield has been calculated by using the aridity indices (X1 and X2 ) and the result in the form of coefficient of determination R2 has been found equal to 0.166. The significance of the regression coefficient has been tested, which shows that the contribution to the yield from aridity index at germination and that at ripening is *** wheat yields are the results of a wide variety of variables, most of which show varying degree of relationship with one another, some positive and some negative in terms of output. These variables may be technology, fertilizers, pesticides, epidemics, kinds of seeds used, market price of crop and the area under cultivation etc, which can be the source of variation in the wheat yield. Since rainfall during germination and temperature at the ripening periods are the necessary factors for the yield of wheat, for this purpose these parameters have been studied in order to their contribution.

关键词： Wea.h.r Yield Model for the Semi Tropical Region Pakistan

hydroelectrolytic and Energetic Replenisher in horses Undergoing Marcha Training

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Open Journal of Veterinary Medicine 2024年第8期14卷 203-216页

作者： José D. Ribeiro Filho Bruna M. Ribeiro Micheline O. Silva Samuel R. Alves Anaïs C. Benitez Waleska M. F. Dantas Marcel F. B. Avanza Raffaella B. C. Teixeira Pedro Ancelmo N. Ermita Laice A. Silva Rinaldo B. Viana.h.lio C. Manso Filho Department of Veterinary Federal University of Viosa Viosa Brazil Institute of Studies of the Wet Tropic Federal University of Southern and Southeastern Par Xinguara Brazil Department of Veterinary Clinic and Surgery Federal University of Minas Gerais Belo Horizonte Brazil Institute of Animal health and Production Federal Rural University of Amazonia Belm Brazil Zootecnics Department Federal Rural University of Pernambuco Recife Brazil

The study aimed to assess the clinical, laboratory, and blood gas analysis of horses undergoing Marcha training and the effects of voluntary ingestion of hydroelectrolytic and energy replenishers after exercise. Eight horses of both genders aged between 5 and 10 years, were included in the study. The exercise consisted of a 10-min warm-up followed by 45 min uninterrupted Marcha on a flat dirt track in the morning. After exercise, the horses received one of the following treatments: Drinking water (control group);hydroelectrolytic and energy replenisher containing sodium chloride, potassium chloride, calcium acetate, magnesium chloride, sodium citrate, dextrose, maltodextrin, and sucrose in three different concentrations (Replenishers A, B, and C). The horses were distributed across the four treatments in a 4 × 4 Latin Squares design using a Split-plot system with 48-hr intervals. Clinical and laboratory evaluations were conducted at four time points: T0 - 5 min before exercise;T1 - up to 5 min after exercise;T2 - 2 hr after starting treatment;and T4 - 4 hr after beginning treatment. Concentrations of urea, creatinine, lactate, phosphorus, and ionized calcium significantly changed after exercise. An increase in blood ph and a decrease in chloride concentrations were observed when replenishers B and C were offered after exercise. The replacements were ingested spontaneously by the animals in a volume greater than that of the control group (water). Replacement B was the most ingested by the animals, demonstrating its greatest potential.

关键词： Dehydration Electrolyte Replacement Exercise Rehydration Voluntary Intake

Investigation on Electron Beam Welded Copper to AISI 316 Stainless Steel Joints

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厦门大学学报（自然科学版） 2002年第S1期41卷 90-91页

作者： El-hebeary M R Megahed h Elziady N Faculty of Engineering Cairo UniversityFaculty of Engineering Cairo UniversityFaculty of Engineering Cairo University Giza EgyptGiza EgyptGiza Egypt

Joints of copper and stainless steels are used in a er ospace applications. Production of these joints by fusion welding faces many dif ficulties. This may be due to the differences in their physical, metallurgical a nd mechanical properties. Electron Beam Welding (EBW) process has been found to be especially well suited in this area. Selection of the appropriate welding par ameters needs thorough investigations. These parameters include: preheat tempera ture (℃), welding current (I w), focusing current (I F), welding spee d (V), height between the gun and workpiece surface (h), scan width (S w) and shift distance (S). The present work aims firstly, setting the pr oper welding conditions to get sound joint between commercially pure copper (C10 200) and AISI 316 stainless steel plates 8 mm thickness. Secondly, investigate t he effect of Electron Beam (EB) shift, single-sided and double-sided welds on the mechanical, metallurgical and chemical properties of the weld bead. Due to t he high difference in thermal conductivity between copper and stainless steel, E lectron Beam (EB) was shifted towards copper with different values. These values were ranged from 0.3 to 0.9 mm in welding without preheating of copper plate an d from 0.1 to 0.4 mm with preheating. Number of joints were welded using variabl e EBW parameters in view to obtain the sound weld bead. These parameters are as follows: gradual reduction I w=51 to 49 mA, I F=845 mA, V=8 mm/sec , h=130 mm, S w=500 μm and S=0.4 mm. The investigation has shown t hat, the copper (C10200) plate must be preheated to get sound welded joint with AISI 316 stainless steel using the EBW process. The tensile fracture in all wel ded samples occurred in copper plate away from the weld bead. This reflects that the weld bead tensile strength is greater than the copper strength. The EB shif t has slight effect on hardness distribution through weld bead. The hardness val ue (h v) reduces in gradual manner from stainless steel hardness to

关键词： AISI Investigation on Electron Beam Welded Copper to AISI 316 Stainless Steel Joints