检索结果-南通市图书馆

Birkhoff Normal Form for the Derivative Nonlinear Schrodinger Equation

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2022年第1期38卷 249-262页

作者： jian Jun liu School of Mathematics Sichuan UniversityChengdu 610065P.R.China

This paper is concerned with the derivative nonlinear Schr?dinger equation with periodic boundary *** obtain complete Birkhoff normal form of order *** an application,the long time stability for solutions of small amp... 详细信息

关键词： Birkhoff normal form derivative nonlinear Schr?dinger equation long time stability

Effect of Glucose-lowering of Heteropolytungstogermanate β-K_6H[GeW_9V_3O_(40)]·9H_2O

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2002年第3期18卷 246-248页

作者： liu Jing fu liu Ju tao MA jian fang CHEN Ya guang LI cai Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China Institute of Basic Applied Medicine Jilin UniversityChangchun 130021P.R.China

Preliminary tests in rats have shown that the title complex is an efficient insulin mimic, which may be the first example of polyoxomatalates possessing insulin mimetic activity.

关键词： Heteropolytungstogermanate Insulin mimetic activity Effect of glucose lowering

Investigation of the role of aziridine bonding agents on the aging of the composite solid rocket propellant(CSRP)

在线全文

学校读者我要写书评

暂无评论

航空动力学报 2008年第11期23卷 2101-2106页

作者： Amged A Ali ZHANG jian-wei cai Guo-biao School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

The role of bonding agents on the aging characteristics is one of the important research *** program of the prepared propellant samples was conducting as follows:Five samples,two free of bonding agents,and three containing an aziridine based bonding agents(MAPO,HX-752,MAT4),four samples based on different bonding and curing agents all were aged at 70 ℃.The prepared bonding agent "MAT4" gave remarkable improvements and resulted in highly stable mechanical properties comparing with HX-752 or *** selected bonding agents family inhibited the rate of decomposition of the propellants during the aging periods and supported the propellant matrix against decomposition at the elevated temperatures.

关键词：氮丙啶黏结剂老化现象复合固体火箭推进剂航空动力系统

Electronic transport properties of Co cluster-decorated graphene

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第6期27卷 81-86页

作者： Chao-Yi cai jian-Hao Chen International Center for Quantum Materials Peking UniversityCollaborative Innovation Center of Quantum Matte

Interactions of magnetic elements with graphene may lead to various electronic states that have potential *** report an in-situ experiment in which the quantum transport properties of graphene are measured with increasing cobalt coverage in continuous ultra-high vacuum environment. The results show that e-beam deposited cobalt forms clusters on the surface of graphene, even at low sample temperatures. Scattering of charge carriers by the absorbed cobalt clusters results in the disappearance of the Shubnikov–de Haas（Sd H） oscillations and the appearance of negative magnetoresistance（MR）which shows no sign of saturation up to an applied magnetic field of 9 T. We propose that these observations could originate from quantum interference driven by cobalt disorder and can be explained by the weak localization theory.

关键词： in situ quantum transport negative magnetoresistance weak localization

Preparation of manganese sulfate from low-grade manganese carbonate ores by sulfuric acid leaching

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 491-500页

作者： Qing-quan Lin Guo-hua Gu Hui Wang Ren-feng Zhu You-cai liu jian-gang Fu School of Minerals Processing and Bioengineering Central South University School of Chemistry and Chemical Engineering Central South University

In this study, a method for preparing pure manganese sulfate from low-grade ores with a granule mean size of 0.47 mm by direct acid leaching was developed. The effects of the types of leaching agents, sulfitric acid concentration, reaction temperature, and agitation rate on the leaching efficiency of manganese were investigated. We observed that sulfuric acid used as a leaching agent provides a similar leach- ing efficiency of manganese and superior selectivity against calcium compared to hydrochloric acid. The optimal leaching conditions in sul- furic acid media were determined; under the optimal conditions, the leaching efficiencies of Mn and Ca were 92.42% and 9.61%, respec- tively. Moreover, the kinetics of manganese leaching indicated that the leaching follows the diffusion-controlled model with an apparent ac- tivation energy of 12.28 kJ·mol-l. The purification conditions of the leaching solution were also discussed. The results show that manganese dioxide is a suitable oxidant of ferrous ions and sodium dimethyldithiocarbamate is an effective precipitant of heavy metals. Finally, through chemical analysis and X-ray diffraction analysis, the obtained product was determined to contain 98% of MnSOa4·H20.

关键词： manganese ore treamaent manganese carbonate leaching leaching kinetics manganese sulfate

Flotation mechanisms of molybdenite fines by neutral oils

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 1-10页

作者： Qing-quan Lin Guo-hua Gu Hui Wang You-cai liu jian-gang Fu Chong-qing Wang jiangxi Copper Technology Research Institute Co.Ltd. Jiangxi Copper Corporation School of Chemistry and Chemical Engineering Central South University School of Minerals Processing and Bioengineering Central South University

The flotation mechanisms of molybdenite fines by neutral oils were investigated through microflotation test, turbidity measure- ments, infrared spectroscopy, and interracial interaction calculations. The results of the flotation test show that at pH 2-11, the floatability of molybdenite fines in the presence of transformer oil is markedly better than that in the presence of kerosene and diesel oil. The addition of transformer oil, which enhances the floatability of molybdenite fines, promotes the aggregation of molybdenite particles. Fourier transform infrared measurements illustrate that physical interaction dominates the adsorption mechanism of neutral oil on molybdenite. Interracial inte- raction calculations indicate that hydrophobic attraction is the crucial force that acts among the oil collector, water, and molybdenite. Strong hydrophobic attraction between the oily collector and water provides the strong dispersion capability of the collector in water. Furthermore, the dispersion capability of the collector, not the interaction strength role in the flotation system of molybdenite fines. Our findings provide between the oily collectors and molybdenite, has a highly significant insights into the mechanism ofmolybdenite flotation.

关键词： molybdenite fines flotation mechanisms neutral oils interfacial interaction hydrophobic attraction

Association of stent thrombectomy and conventional treatment with neuroprotection, complications, anxiety, and depression in acute ischemic stroke patients

在线全文

学校读者我要写书评

暂无评论

World Journal of Psychiatry 2025年第1期15卷 72-82页

作者： Kai-Jie Yang Jia-jian Huang cai-Xia Xuan Department of Neurology Qinzhou Second People's HospitalQinzhou 535000Guangxi Zhuang Autonomous RegionChina

BACKGROUND Acute ischemic stroke(AIS)is an abrupt blood flow cessation to a specific brain region within a vascular zone,causing a subsequent decline in neurological *** thrombectomy is a recently established technique for treating *** provides the benefits of being a relatively simple and safe procedure,capable of partially enhancing a patient’s ***,some patients may experience endothelial damage and recurrent thrombosis,with clinical outcomes that are not always ***,the efficacy of this method remains *** To survey the association of stent thrombectomy vs standard treatment with neurological function protection,complications,and short-term prognosis in patients diagnosed with *** This study assigned 90 patients with AIS to the observation and control groups(n=45 patients)from December 2020 to December *** thrombectomy was conducted in the observation group,whereas routine treatment was provided to the control *** study assessed the therapeutic outcomes of two groups,including a comparison of their neurological function,living ability,anxiety and depression status,plaque area,serum inflammatory factors,serum Smur100βprotein,neuron-specific enolase(NSE),homocysteine(Hcy),and vascular endo-thelial ***,the incidence of complications was calculated and analyzed for each *** The total effective rate of treatment was 77.78%and 95.56%in the control and observation groups,*** 8 weeks of treatment,the scores on the National Institutes of Health Stroke Scale,Hamilton Anxiety Scale,and Hamilton Depression Scale decreased remarkably;the Barthel index increased remarkably,with better improvement effects of the scores in the observation group(P<0.05);total cholesterol,triglyceride,C-reactive protein,and plaque area lessened remarkably,with fewer patients in the observation group(P<0.05);S-100βprotein,NSE,and Hcy levels lessened remarkably,with fewer patients in

关键词： Stent thrombectomy Acute ischemic stroke Neurological function Complications Short-term prognosis

Manifestation of Quantum Chaos in the Spectra of Quantum Well with Tilted Magnetic Field

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1999年第2期16卷 140-142页

作者： liu Bo DAI jian-hua ZHANG Guang-cai ZHANG Hong-jun Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

Two statistical properties,the nearest neighbor energy level spacing distribution P(s)and the spectral rigidityΔ3(L),are reported for energy level of a quantum well in a tilted magnetic ***-reversal(T)symmetry is broken in the *** system is invariant under the anti-unitary combination of symmetric operations which include T,leading to what is called false *** the increasing magnetic field,P(s)andΔ3(L)change from Brody type-like distribution to the Gaussian orthogonal ensemble(GOE)*** result is a clear manifestation of quantum chaos in the system and is in agreement with the prediction of which the false T-violation suffices to give the energy spectra the properties of the GOE,instead of the Gaussian unitary ensemble(GUE).The result indicates that the system translates from mixed-type state to quantum chaotic ***,the spectral rigidityΔ3(L)turns into GUE with the magnetic field *** different demonstration of P(s)and theΔ3(L)is due to the counting of only finite semi-classical orbits.

关键词： field. quantum unitary

Benchmark evaluation of tomographic algorithms for simultaneous reconstruction of temperature and volume fraction fields of soot and metal-oxide nanoparticles in non-uniform flames

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2021年第2期64卷 237-250页

作者： SHUI ChongYuan liu HeCong cai WeiWei Key Laboratory for Power Machinery and Engineering of Ministry of Education School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

With the growing applications of nanofluid flame, the monitoring and controlling of its combustion process is of paramount importance. Thus, it is necessary to develop diagnosing methods which can simultaneously image important parameters such as temperature and volume fractions of soot, metal-oxide nanoparticles. Tomographic emission spectroscopy is an effective method which has been proposed for this purpose. However, the inversion process was only reported with least-squares QR decomposition(LSQR) so far and there are numerous well-established reconstruction algorithms which have not been utilized ***, this work aims to perform systematic comparative studies on several representative algorithms for the inversion process. In the simulative studies, algorithms including Tikhonov regularization, algebraic reconstruction technique(ART), LSQR,Landweber algorithm, maximum likelihood expectation maximization(MLEM), and ordered subset expectation maximization(OSEM) were discussed. The effects of the number of iterations, the signal-to-noise ratio, and the number of projections and the calibration error in projection angles on the performance of the algorithms were investigated. Advice on selecting the suitable algorithms under different application conditions is then provided according to the extensive numerical studies.

关键词： inverse analysis algorithms temperature field soot and metal-oxide volume fraction non-uniform nanofluid flame