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A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi Yu Tao Yu jian-hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Crushing behaviors of buckling-induced metallic meta-lattice structures

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Defence Technology（防务技术） 2022年第8期18卷 1301-1310页

作者： jian-hua Dong Yong-jun Wang Feng-nian Jin hua-lin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Department of Civil Engineering Nanyang Institute of TechnologyNanyang473004China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

Thin-walled lattice materials can be applied as energy absorbers in protective structures of civil defense. In this paper, quasi-static in-plane crushing tests were carried out to investigate the crushing behavior and energy absorption of buckling induced meta-lattice structures (BIMSs) with different central angles made of plastic iron material DT3 and formed by wire cutting technique. Three crushing patterns were revealed and analyzed. The test results clearly show that the initial peak force (IPF), the crushing force efficiency (CFE), the specific energy absorption (SEA) and the mean crushing force (MCF) can be substantially improved by introducing buckling pattern into the straight-walled lattice structure. The MCF of the BIMS was consistently predicted based on the simplified super folding element (SSFE) and the flattening element.

关键词： Buckling induced meta-lattice structure (BIMS) Crushing force efficiency

Modeling and Control for Magnetostrictive Hysteresis

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Chinese Journal of Aeronautics 2006年第B12期19卷 146-150页

作者： MAO jian-qin MAYan-hua The Seventh Research Division Beijing University of Aeronautics and Astronautics Beijing 100083 China

To deal with the rate-dependent hysteresis presented in a magnetostrictive actuator, a new method of modeling and control is proposed. The relationship between inputs and outputs of the actuator is approximately described by a dynamic differential equation with two rate-dependent coefficients, each expressed as a polynomial of frequency. For a given frequency, the coefficients will be able to be estimated by approximating the experimental data of the outputs of the magnetostrictive actuator. Based on this model, a quasi-PID controller is designed. In the space of the coefficients and frequency, the stable domain of closed loop system with hysteresis is analyzed. The numerical simulation and experiments have born witness to the feasibility of the proposed new method.

关键词： mechatronics engineering quasi-PID controller modeling magnetostrictive hysteresis

Nonmetallic Inclusion Control of 350 km/h High Speed Rail Steel

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Journal of Iron and Steel Research International 2009年第3期16卷 20-26,36页

作者： ZHAO Ke-wen ZENG jian-hua WANG Xin-hua School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing100083 China Panzhihua Iron and Steel (Group) Co Panzhihua 617067 Sichuan China

Inclusion has an important effect on quality of high speed rail steel. In consideration of the lower acceptance percentage of the inclusion and its constraint against the requirement for large scale production of 350 km/h high speed rail steel in Panzhihua Iron and Steel （Group） Co,the technology of nonmetallic inclusion control for 350 km/h high speed rail steel was studied. An optimized model of the argon-blowing in ladle furnace （LF）,the control of the components of the ladle slag,and the technique of calcium treatment for the molten steel was brought forward. Using the researched technology,the removal ratio of the inclusion was increased and the components,distribution,and shape of the inclusion in the rail steel were changed,which resulted in a reduction in the average total oxygen content to 10.17×10^-6 and an increase in the comprehensive acceptance percentage of the nonmetallic inclusion from 48.21% to 98.1%. Test has shown that this metallurgical technology can meet the requirement for large scale production of 350 km/h high speed steel in Panzhihua Iron and Steel （Group） Co.

关键词： high Speed rail steel inclusion refining calcium treatment total oxygen content

Cell search algorithms for the 3G long-term evolution

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 33-37页

作者： SU huan ZHANG jian-hua Wireless Technology Innovation of Institute Beijing University of Posts and Telecommunications Beijing 100876 China

This article presents downlink initial synchronization and cell identification algorithms for long term evolution （LTE） of third-generation （3G） mobile communication systems, which are based on synchronization channel （SCH） and cell specific pilot symbols, respectively. The key features of the proposed scheme are： it can improve performance of the frequency synchronization through oversampling of the SCH, it can support a large number of target cells by modulating a cell-specific pilot sequence over two symbols within a subframe, and it can guarantee cell identification performance by maximally ratio combining the frequency domain differential cross-correlation. Simulations show that the proposed scheme has a potential use in 3G LTE.

关键词： 3rd generation partnership project (3GPP) LTE orthogonal frequency division multiple access (OFDMA) cell search oversampling

Comparative study on pullout behaviour of pressure grouted soil nails from field and laboratory tests

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Journal of Central South University 2013年第8期20卷 2285-2292页

作者： HONG Cheng-yu YIN jian-hua PEI hua-fu Department of Civil Engineering Shantou University Shantou 515063 China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

Pullout resistance of a soil nail is a critical parameter in design and analysis for geotechnical engineers. Due to the complexity of field conditions, the pullout behaviour of cement grouted soil nail in field is not well investigated. In this work, a number of field pullout tests of pressure grouted soil nails were conducted to estimate the pullout resistance of soil nails. The effective bond lengths of field soil nails were accurately controlled by a new grouting packer system. Typical field test results and the related comparison with typical laboratory test results reveal that the apparent coefficient of friction （ACF） decreases with the increase of overburden soil pressure when grouting pressure is constant, but increases almost linearly with the increase of grouting pressure when overburden pressure （soil depth） is unchanged. Water contents of soil samples at soil nail surfaces show obvious reductions compared with the results of soil samples from drillholes. After soil nails were completely pulled out of the ground, surface conditions of the soil nails and surrounding soil were examined. It is found that the water content values of the soil at the soil/nail interfaces decrease substantially compared with those of soil samples extracted from drillholes. In addition, all soil nails expand significantly in the diametrical direction after being pulled out of ground, indicating that the pressurized cement grout compacts the soil and penetrates into soil voids, leading to a corresponding shift of failure surface into surrounding soil mass significantly.

关键词： soil nail apparent coefficient of friction overburden soil pressure grouting pressure

基于反应气混合物的ICP-MS/MS测定原油中的钒和镍

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光谱学与光谱分析 2025年第1期45卷 101-106页

作者：蔡松韬黄莹秀袁亮代宇宣莫垚坤黄建华湖南工学院材料科学与工程学院湖南衡阳421002 湖南省中医药研究院中药研究所湖南长沙410013

原油中金属元素钒和镍(V和Ni)的含量和比值可为深入了解原油的沉积环境特征和有机质类型发挥重要作用。在原油炼制过程中,V和Ni作为原油催化裂化过程中的有害金属元素,会降低催化剂的活性,严重时会导致催化剂中毒,会严重腐蚀设备,在精... 详细信息

原油中金属元素钒和镍(V和Ni)的含量和比值可为深入了解原油的沉积环境特征和有机质类型发挥重要作用。在原油炼制过程中,V和Ni作为原油催化裂化过程中的有害金属元素,会降低催化剂的活性,严重时会导致催化剂中毒,会严重腐蚀设备,在精炼之前必须对原油中的V和Ni进行脱除处理。V和Ni具有致突变性和致癌性,识别或监测原油中V和Ni进入环境的潜在危险变得越来越重要,对原油中V和Ni的含量进行高灵敏精准测定具有重要意义。采用电感耦合等离子体串联质谱(ICP-MS/MS)测定原油中V和Ni的新策略。原油样品经航空煤油简单稀释后直接采用ICP-MS/MS进行分析,针对V和Ni受到的质谱干扰,在MS/MS模式下,采用由NH_(3)/He(He为缓冲气)和H_(2)组成的反应气混合物(NH_(3)/He/H_(2))作为反应气,基于V^(+)与NH_(3)/He/H_(2)不发生反应,而V^(+)的干扰离子与NH_(3)/He/H_(2)发生反应,采用原位质量法消除干扰,选择V^(+)进行测定;基于Ni^(+)与NH_(3)/He/H_(2)发生反应,采用质量转移法消除干扰,选择无干扰团簇离子Ni(NH_(3))_(3)^(+)进行测定。通过与NH_(3)/He反应模式进行对比研究发现,对于V的测定,加入H_(2)为反应气能快速去除氩基离子的干扰,并能协同NH_(3)消除氧化物离子的干扰;对于Ni的测定,加入H_(2)为反应气能促进全氢加合物(-NH_(3))的形成,从而提高生成Ni(NH_(3))_(3)^(+)的产率。在NH_(3)/He/H_(2)反应模式下,V和Ni的背景等效浓度(BEC)更低,Ni的灵敏度更高,V和Ni的检出限(LOD)分别低至0.83和3.76 ng·kg^(-1),定量限(LOQ)分别为2.77和12.5 ng·kg^(-1)。通过分析标准参考物质NIST SRM 1634c并进行加标回收实验评价方法的准确度和精密度,结果显示,方法的测定结果与标准参考物质的认证值基本一致,V和Ni的加标回收率分别为97.7%和103%,相对标准偏差(RSD)分别为1.8%和1.9%。所建立的分析方法避免了繁琐的样品预处理过程,具有操作简单快速、灵敏度高、准确度和精密度好的特点,适用于原油中V和Ni的检测,能为原油深加工中V和Ni的脱除提供理论依据。

关键词：原油电感耦合等离子体串联质谱钒(V) 镍(Ni) 氨气/氦气/氢气(NH_(3)/He/H_(2))

Calcineurin inhibitors and nephrotoxicity in children

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World Journal of Pediatrics 2018年第2期14卷 121-126页

作者： Fei Liu jian-hua Mao Department of Nephrology Children's HospitalZhejiang University School of MedicineHangzhou 310003China

Background Calcineurin inhibitors(CNIs)are commonly given to transplant recipients of kidneys and other solid organs and to patients with immune disorders,such as steroid-resistant nephrotic syndrome,steroid-dependent nephrotic syndrome,and frequent relapse nephrotic *** CNIs remain the most effective available immunosuppressant agent,there is clinical concern regarding possible long-term *** concern is especially significant in children who have a longer life expectancy and greater growth *** sources In this review,we analyzed the literatures to identify original articles that examined use of CNIs in children who received organ transplantation and nephropathy to assess the available evidence of their ***,Elsevier,and Tompson ISI Web of Knowledge were searched for identifying relevant *** Clinical research supports the presence of CNI-related ***,some researchers have questioned the prevalence and seriousness of chronic CNIs nephrotoxicity,especially because the pathological lesions typically associ-ated with long-term CNI use are *** researchers have focused on early markers of CNI nephrotoxicity,and the methods that may help prevent and manage *** Future research should focus on investigating early markers of CNI nephrotoxicity and strategies for improved immunosuppressant therapy,and developing alternative ***-mediated nephrotoxicity should always be taken seriously in clinic.

关键词： Calcineurin inhibitors(CNIs) Children Nephrotic syndrome Nephrotoxicity Transplantation

A Variation of a Conjecture Due to Erds and Sós

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Acta Mathematica Sinica,English Series 2009年第5期25卷 795-802页

作者： jian hua YIN Jiong Sheng LI Department of Mathematics School of Information Science and Technology Hainan University Haikou 570228 P.R. China Department of Mathematics University of Science and Technology of China Hefei 230026 P.R. China

Erdoes and Soes conjectured in 1963 that every graph G on n vertices with edge number e（G）〉 1/2（k - 1）n contains every tree T with k edges as a subgraph. In this paper, we consider a variation of the above conjecture, that is, for n 〉 9/ 2k^2 ＋ 37/2＋ 14 and every graph G on n vertices with e（G）〉 1/2 （k- 1）n, we prove that there exists a graph G＇ on n vertices having the same degree sequence as G and containing every tree T with k edges as a subgraph.

关键词： graph degree sequence Erdoes-Soes conjecture