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Leaching process of germanium oxide dust

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Rare Metals 2008年第6期27卷 555-559页

作者： liang Jie WANG hua Department of Materials and Metallurgical Engineering Kunming University of Science and Technology Kunming 650093 China Chemistry Department Bo＇ie University Bijie 5511700 China

A thermodynamic analysis on the acid leaching process of germanium oxide dust and discussion on the behaviors of main substances of the dust in the leaching process were carried out. The effects of temperature, acid concentration, leaching time and stirring speed on the leaching rate of germanium were investigated. Based on the characteristic of the dust, the kinetics and reactive mechanism of acid leaching were studied. The results show that the leaching of the dust by acid belonged to ＂the unreacted core shrinking model＂ of producing solid outgrowth layer. The chemical reaction was controlled by inner diffusion process. The apparent activation energy of leaching process was 12.60 kJ/mol. The leaching reaction of germanium was determined to be mainly second order reaction. The optimum conditions were the reaction temperature of 363 K, the leaching time of 2.5 h, the stirring speed of 120 r/min, the solid-to-liquid ratio of 1/8 and the acid concentration of 120 g/L. Under these conditions, the leaching rate of germanium can come up to more than 87%.

关键词： non-ferrous metallurgy leaching process kinetics metallurgical principle germanium oxide dust thermodynamics

A New Model Potential Acting on the Excited Electron Within Molecules： Application to Calculate the Recurrence Spectra of Excited H2 Molecules in Strong External Fields

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Chinese Physics Letters 2004年第7期21卷 1191-1194页

作者： WANGDe-hua DINGShi-liang SchoolofPhysicsandMicroelectronics ShandongUniversityJinan250100

By using the molecular orbit theory, we give a new model potential acting on the excited electron within a molecule. The potential is the total interaction energy of this electron with all the nuclei and other electrons. We find that the introduction of a new model potential results in an extreme increase of the number of closed orbits as compared to the hydrogen atom. Making use of the molecular closed-orbit theory (MCOT) and the new model potential, we calculate the recurrence spectra of H2 molecules in parallel electric and magnetic fields for different quantum defects. The modulations in the spectra can be analysed in terms of the scattering of the excited electron on the molecular core. Our results are in good agreement with the quantum results.

关键词： Atomic and molecular physics Computational physics

S空位及非金属掺杂单层Bi_(2)S_(2)Se的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 127-134页

作者：张建华王敏陈畅曹倩徐银湖北大学资源环境学院武汉430062

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性... 详细信息

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性后出现了晶格缺陷.含S空位和P、Cl、Br掺杂体系的带隙减少,而I掺杂体系的带隙增加.同时,含S空位和Cl、Br、I掺杂体系的费米能级穿过导带底,而P掺杂体系的费米能级穿过价带顶.所有改性体系在费米能级附近都出现了缺陷能级或杂质能级,表现出较高的可见光吸收能力和散射能力,改性体系的对可见光的吸收能力和散射能力有所增加.

关键词： Bi_(2)S_(2)Se 掺杂电子结构光学性质第一性原理

Girvanella fossils from the Phanerozoic:Distribution,evolution and controlling factors

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Journal of Palaeogeography 2024年第4期13卷 924-938页

作者： hua-Shan Zhang Ming-Yue Dai Yong-An Qi Lan-Lan Han Zhong-Lei yin Song-hua Chen liang-Biao Lin Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059Sichuan ProvinceChina School of Resources and Environment Henan Polytechnic UniversityJiaozuo 454003Henan ProvinceChina

Girvanella is one of the common genera of cyanobacteria that plays a monumental role in the evolution of life on Earth and the formation of *** on a detailed search in the literature of Girvanella fossils,we have compiled a global database of Girvanella fossils and revealed the evolution of Girvanella fossils throughout the *** species,Girvanella kasakiensis,Girvanella problematica,Girvanella wetheredii,and Girvanella staminea,are recognized and *** data show that Girvanella fossils have well-defined temporal distribution during the Paleozoic Era,have a significant temporal gap in the Mesozoic Era,and have only been recorded sporadically in the Cenozoic *** were relatively abundant during the Cambrian Epoch 2-Early Ordovician,Late Ordovician,Late Devonian-Mississippian,and tended to lesser degrees during the Silurian-Early Devonian,Lopingian Epoch-Middle Jurassic,and Cretaceous-Present ***,the evolution of the abundance and diversity of Girvanella fossils was fundamentally consistent and showed episodical declining during the *** further explore these relationships,we thoroughly compared them with environmental factors such as seawater carbonate saturation state,Ca^(2+)concentration,pH values,and atmospheric partial pressure of carbon dioxide(p CO_(2)).This study indicates that seawater carbonate saturation state and Ca^(2+)concentration are major controls on secular patterns of the abundance and diversity of Girvanella fossils,together with the secondary factors of pH values and p CO_(2).Considering the long history of Girvanella fossils,their abundance and diversity offer the potential to assist the interpretation of the long-term evolution of marine and atmosphere components during the Phanerozoic.

关键词： Girvanella Temporal distribution Abundance Diversity Control factors

Development of a Derivatization-free GC-FID Method for Evaluation of Free Fatty Acid Levels in Plasma of Diabetic Nephropathy Patients

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Chemical Research in Chinese Universities 2011年第4期27卷 578-583页

作者： hua Hai-yin liang Qiong-lin CHEN Jun WANG Yi-ming LI Ping LUO Guo-an Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China Institute of Clinical Medical Science China-Japan Friendship Hospital Beijing 100029 P. R. China

Metabolism of free fatty acids（FFAs） is related to several important physiological events and therefore their quantitaion in biological samples arouses extensive interest and *** gas chromatography with flame ionization detector（GC-FID） methods for the analysis of FFAs normally require derivatization of them in order to lower boiling *** this extra procedure tends to induce additional error and it is laborious and time-consuming.A derivatization-free method was therefore established in the present investigation to determine FFAs in human plasma by capillary（GC-FID）.After extraction of FFAs from plasma,a highly polar FFAP（free fatty acid in plasma） column was employed to directly quantitate FFAs concentration,free from derivatization *** sample pretreatments were carried out at room temperature,improving recovery of short-chain *** acid（C17：0） was employed as internal standard,and the proposed method was validated for recovery,precision,sensitivity,stabi-lity,and *** data show that it is suitable for clinical study that has been applied to the evaluation of FFAs levels in plasma of diabetic nephropathy（DN） patients during the course of ***-seven patients diagnosed with DN were admitted to the double-blind *** group（n=17） underwent solely basic treatment and the patients did not show significant change in FFAs concentration during six months of *** group（n=30） was supplied with traditional Chinese medicine besides basic *** six months of medication,their plasma concentration of palmitic acid（C16：0）,stearic acid（C18：0） and oleic acid（C18：1n-9） decreased while linolenic acid（C18：3n-3） increased significantly（P〈0.05）.These four compounds could be served as biomar-kers in the evaluation of drug efficacy,and their quantitation in plasma may provide additional information for disease progression in DN patients.

关键词： Derivitizaiton-free gas chromatography with flame ionization detector(GC-FID) Free fatty acid(FFA) Di-abetic nephropathy(DN)

Multi-disciplinary design optimization with variable complexity modeling for a stratosphere airship

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Chinese Journal of Aeronautics 2019年第5期32卷 1244-1255页

作者： Shi yin Ming ZHU Haoquan liang School of Aeronautic Science and Engineering Beihang University School of Automation Science and Electrical Engineering Beihang University

This paper proposes a hybrid architecture based on Multi-disciplinary Design Optimization(MDO) with the Variable Complexity Modeling(VCM) method, to solve the problem of general design optimization for a stratosphere airship. Firstly, MDO based on the Concurrent SubSpace Optimization(CSSO) strategy is improved for handling the subsystem coupling problem in stratosphere airship design which contains aerodynamics, structure, and energy. Secondly, the VCM method based on the surrogate model is presented for reducing the computational complexity in high-fidelity modeling without loss of accuracy. Moreover, the global-to-local optimization strategy is added to the architecture to enhance the process. Finally, the result gives a prominent stratosphere airship general solution that validates the feasibility and efficiency of the optimization architecture. Besides, a sensitivity analysis is conducted to outline the critical impact upon stratosphere airship design.

关键词： Multi-disciplinary design optimization Sensitivity analysis Stratosphere airship Surrogate model Variable complexity modeling

Strong interactions of incident shock wave with boundary layer along compression corner

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Chinese Journal of Aeronautics 2020年第12期33卷 3149-3157页

作者： Shanguang GUO Yun WU hua liang Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China

The coherent structure and instability of the interaction of incident shock wave with boundary layer developing on a compression corner are experimentally *** experiments are carried out in a supersonic wind tunnel of Mach number *** attention is paid to shock patterns and unsteady shock motions induced by the separation *** high-speed schlieren is used to visualize the flowfield evolution and to characterize the *** snapshot proper orthogonal decomposition of schlieren sequences is applied to investigate the primary coherent structure in the *** Fourier transform and continuous wavelet transformation are applied to characterize the *** results show that there are large-scale low-frequency oscillations of the shock waves and small-scale high-frequency pulsations in the separation *** peak frequency of shock oscillation is mainly concentrated in the range of 100–1000 *** pulsation of the small flow structure in the separation bubble is mainly concentrated above 12.5 k *** on the results of experimental analysis,the preliminary mechanism of the largescale instability of such interaction is obtained.

关键词： Shock wave Boundary layer Interaction Flow mechanism Instability

Applying the model driven generative domain engineering method to develop self-organizing architectural solutions for mobile robot

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1652-1661页

作者： liang Hai-hua ZHU Miao-liang School of Computer Science and Technology Zhejiang University Hangzhou 31002 7 China

Model driven generative domain engineering (MDGDE) is a domain engineering method aiming to develop optimized, reusable architectures, components and aspects for application engineering. Agents are regarded in MDGDE as special objects having more autonomy, and taking more initiative. Design of the agent involves three levels of activities: logical analysis and design, physical analysis, physical design. This classification corresponds to domain analysis and design, application analysis, and application design. Agent is an important analysis and design tool for MDGDE because it facilitates development of complex distributed system—the mobile robot. According to MDGDE, we designed a distributed communication middleware and a set of event-driven agents, which enables the robot to initiate actions adaptively to the dynamical changes in the environment. This paper describes our approach as well as its motivations and our practice.

关键词： Domain engineering Agent oriented software engineering Mobile robot

A human embryonic stem cell-based in vitro model revealed that ultrafine carbon particles may cause skin inflammation and psoriasis

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Journal of Environmental Sciences 2020年第1期32卷 194-204页

作者： Zhanwen Cheng Xiaoxing liang Shaojun liang Nuoya yin Francesco Faiola State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Enuironmental SciencesChinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Air pollution has been linked to many health issues,including skin conditions,especially in *** all the atmospheric pollutants,ultrafine particles have been deemed very dangerous since they can readily penetrate the lungs and skin,and be absorbed into the ***,we employed a human embryonic stem cell(h ESC)-based differentiation system towards keratinocytes,to test the effects of ultrafine carbon particles,which mimic ambient ultrafine particles,at environment related *** found that10 ng/mL to 10μg/mL ultrafine carbon particles down-regulated the expression of the pluripotency marker SOX2 in h ***,1μg/mL to 10μg/mL carbon particle treatments disrupted the keratinocyte differentiation,and up-regulated inflammationand psoriasis-related genes,such as IL-1β,IL-6,CXCL1,CXCL2,CXCL3,CCL20,CXCL8,and S100 A7 and S100 A9,***,our results provide a new insight into the potential developmental toxicity of atmospheric ultrafine particles.

关键词： Human embryonic stem cells(hESCs) Keratinocytes Ultrafine carbon particles Inflammation Psoriasis Developmental toxicity