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A Series of Variable Separation Solutions and New Soliton Structures of （2＋1）-Dimensional Korteweg-de Vries Equation

作者： JIANG Xiao-yan ZHANG Ji-long ZOU Wei chang zhi-yuan

U/U of the environmental sample can indicate the existence of uranium irradiation,and even can be uesd to estimate the burnup of nuclear spent fuel.A study on the burnup estimation of irradiated uranium which was mixed with natural uranium was carried out by measuring the U/U and U/U in the samples by using MC-ICP-MS. According to the equation(1) and(2),a programme for calculating the burnup of the irradiated

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Communications in Theoretical Physics 2006年第3X期46卷 403-406页

作者： XU chang-zhi Department of Physics Jinhua Education College Jinhua 321000 China

Variable separation approach is introduced to solve the （2＋1）-dimensional KdV equation. A series of variable separation solutions is derived with arbitrary functions in system. We present a new soliton excitation model （24）. Based on this excitation, new soliton structures such as the multi-lump soliton and periodic soliton are revealed by selecting the arbitrary function appropriately.

关键词： variable separation approach (2+1)-dimensional KdV equation new soliton excitation

A gauge theory for two-band model of Chern insulators and induced topological defects

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Communications in Theoretical Physics 2022年第1期74卷 124-133页

作者： zhi-Wen chang Wei-chang Hao Xin Liu Institute of Theoretical Physics Faculty of SciencesBeijing University of TechnologyBeijing 100124China School of Physics Beihang UniversityBeijing 100191China

In this paper a gauge theory is proposed for the two-band model of Chern *** on the so-calle't Hooft monopole model,a U(1)Maxwell electromagnetic sub-field is constructed from an SU(2)gauge field,from which arise two types of topological defects,monopoles and e2 *** focus on the topological number in the Hall conductance σ_(xy)=e^(2)/hC,where C is the Chern *** is discovered that in the monopole case C is indeterminate,while in the meron case C takes different values,due to a varying on-site energy *** a typical example,we apply this method to the square lattice and compute the winding numbers(topological charges)of the defects;the C-evaluations we obtain reproduce the results of the usual ***,based on the gauge theory we propose a new model to obtain the high Chern numbers|C|=2,4.

关键词： Chern insulator Chern number monopole meron

Organic acid anions:An effective defensive weapon for plants against aluminum toxicity and phosphorus deficiency in acidic soils

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Journal of Genetics and Genomics 2016年第11期43卷 631-638页

作者： zhi chang Chen Hong Liao Root Biology Center Fujian Agriculture and Forestry University

Aluminum （AI） toxicity and phosphorous （P） deficiency are two major limiting factors for plant growth on acidic soils. Thus, the physiological mechanisms for AJ tolerance and P acquisition have been intensively studied. A commonly observed trait is that plants have developed the ability to utilize organic acid anions （OAs; mainly malate, citrate and oxalate） to combat AI toxicity and P deficiency. OAs secreted by roots into the rhizosphere can externally chelate Al^3＋ and mobilize phosphate （Pi）, while OAs synthesized in the cell can internally sequester Al^3＋ into the vacuole and release free Pi for metabolism. Molecular mechanisms involved in OA synthesis and transport have been described in detail. Ensuing genetic improvement for AI tolerance and P efficiency through increased OA exudation and/or synthesis in crops has been achieved by transgenic and marker-assisted breeding. This review mainly elucidates the crucial roles of OAs in plant Al tolerance and P efficiency through summarizing associated physiological mechanisms, molecular traits and genetic manipulation of crops.

关键词： Organic acid anions Al toxicity P defidency Acidic soils

Minimizing pest aluminum in magnesium for the production of high-purity titanium

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Journal of Magnesium and Alloys 2023年第11期11卷 4189-4196页

作者： Bo Yang Rui Zheng Ge Wu zhi-Min chang zhi-Wei Shan Engineering Research Center for Magnesium-based New Materials Center for Advancing Materials Performance from the Nanoscale(CAMP-Nano)State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049PR China

It is practically difficult to find titanium sponges with low and stable aluminum impurities on the market even though it is the precondition to prepare high-purity titanium. Analysis indicates that almost all the aluminum impurities in the titanium sponge are inherited from the magnesium used to reduce titanium tetrachloride. However, it remains elusive for decades why magnesium produced through the silicothermic reduction method contains a high content of aluminum impurities with large fluctuations. By recourse to thermodynamic calculations and comparative experiments, we demonstrate that fluorite, a material used as a catalyst in the silicothermic reduction method to produce magnesium, is the chief culprit for the pest aluminum and propose a mechanism to rationalize the observed phenomena. Our findings indicate that one practical way to produce qualified magnesium for the production of high-purity titanium is to abandon fluorite during the production of magnesium with the silicothermic reduction method.

关键词： High-purity titanium Titanium sponge Magnesium Aluminum impurity Silicothermic reduction

Mitogen-activated protein kinase signaling pathway and invasion and metastasis of gastric cancer

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World Journal of Gastroenterology 2015年第41期21卷 11673-11679页

作者： Mei Yang chang-zhi Huang Department of Etiology and Carcinogenesis & State Key Laboratory of Molecular Oncology Cancer Institute and Hospital Chinese Academy of Medical Sciences and Peking Union Medical College

The mortality rate of gastric cancer worldwide is as high as 70%, despite the development of novel therapeutic strategies. One reason for the high mortality is the rapid and uninhibited spread of the disease, such that the majority of patients are diagnosed at a stage when efficient therapeutic treatment is not available. Therefore, in-depth research is needed to investigate the mechanism of gastric cancer metastasis and invasion to improve outcomes and provide biomarkers for early diagnosis. The mitogen-activated protein kinase(MAPK) signaling pathway is widely expressed in multicellular organisms, with critical roles in multiple biological processes, such as cell proliferation, death, differentiation, migration, and invasion. The MAPK pathway typically responds to extracellular stimulation. However, the MAPK pathway is often involved in the occurrence and progression of cancer when abnormally regulated. Many studies have researched the relationship between the MAPK signaling pathway and cancer metastasis and invasion, but little is known about the important roles that the MAPK signaling pathway plays in gastric cancer. Based on an analysis of published data, this review aims to summarize the important role that the MAP kinases play in the invasion and metastasis of gastric cancer and attempts to provide potential directions for further research and clinical treatment.

关键词： Mitogen-activated protein kinase Gastric cancer Si

Study on （2＋1）-Dimensional Nizhnik-Novikov-Veselov Equation by Using Extended Mapping Approach

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Communications in Theoretical Physics 2006年第1X期46卷 10-14页

作者： XU chang-zhi HE Bao-Gang Department of Physics Jinhua Education College Jinhua 321000 China

Extended mapping approach is introduced to solve （2＋1）-dimensional Nizhnik-Novikov Veselov equation. A new type of variable separation solutions is derived with arbitrary functions in the model. Based on this excitation, rich localized structures such as multi-lump soliton and ring soliton are revealed by selecting the arbitrary function appropriately.

关键词： extended mapping approach (2+1)-dimensional Nizhnik-Novikov-Veselov equation new localized excitation

Organic functional materials based buffer layers for efficient perovskite solar cells

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Chinese Chemical Letters 2017年第3期28卷 503-511页

作者： Fateh Ullah Hongzheng Chen chang-zhi Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

In this review, we highlight the recent development of organic π-functional materials as buffer layers in constructing efficient perovskite solar cells（PVSCs）. By following a brief introduction on the PVSC development, device architecture and material design features, we exemplified the exciting progresses made in field by exploiting organic π-functional materials based hole and electron transport layers（HTLs and ETLs） to enable high-performance PVSCs.

关键词： Perovskite solar cells Organic functional material Hole transport layer Electron transport layer Power conversion efficiency

A possible explanation for the electron/positron excess of ATIC/PAMELA

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Research in Astronomy and Astrophysics 2010年第1期10卷 39-46页

作者： Rui-zhi Yang Jin chang Jian Wu Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

Results from PAMELA and ATIC indicate that the Kaluza-Klein type dark matter particles could be the annihilation source of the observed excess of electrons and positrons. Assuming the existence of a nearby black hole with 10000-100000 solar masses and a point source boost algorithm, we apply the standard propagation model and find that the results fit the data well.

关键词： dark matter - black hole physics - cosmic rays

Pyrolyzed bacterial cellulose/graphene oxide sandwich interlayer for lithium–sulfur batteries

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Rare Metals 2017年第5期36卷 418-424页

作者： Yu-Di Shen zhi-chang Xiao Li-Xiao Miao De-Bin Kong Xiao-Yu Zheng Yan-Hong chang Lin-Jie zhi Chinese Academy of Sciences Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology Beijing 100190China Department of Environmental Engineering University of Science and Technology of BeijingBeijing 100083China Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants University of Science and Technology of BeijingBeijing 100083China Institute of Forensic Science Ministry of Public SecurityBeijing 100038China

Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as precursor. The unique and delicate structure where three-dimensional interconnected bacterial cellulose（BC） network embedded in two-dimensional GO skeleton could not only work as an effective barrier to retard polysulfide diffusion during the charge/discharge process to enhance the cyclic stability of the Li–S battery, but also offer a continuous electron transport pathway for the improved rate *** a result, by utilizing pure sulfur as cathodes, the Li–S batteries assembled with PBC/GO interlayer can still exhibit a capacity of nearly 600 mAh·g^-1 at 3C and only 0.055% capacity decay per cycle can be observed over 200 cycles. Additionally, the cost-efficient and environmentfriendly raw materials may enable the PBC/GO sandwich interlayer to be an advanced configuration for Li–S batteries.

关键词： Biomass materials Graphene oxide Separator Lithium–sulfur batteries