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Moments of Continuous-state Branching Processes with or Without Immigration

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 361-373页

作者： li-na ji Zeng-hu li Department of Mathematics Southern University of Science and TechnologyShenzhen 518055China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China

For a positive continuous function f satisfying some standard conditions,we study the f-moments of continuous-state branching processes with or without *** main results give criteria for the existence of the *** chara... 详细信息

关键词： branching process continuous-state immigration moments stochastic equation

Symmetry Reduction and Cauchy Problems for a Class of Fourth-Order Evolution Equations

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Communications in Theoretical Physics 2008年第7期50卷 31-38页

作者： li ji-na ZHANG Shun-li Center for Nonlinear Studies Department of Mathematics Northwest University Xi＇an 710069 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

We exploit higher-order conditional symmetry to reduce initial-value problems for evolution equations toCauchy problems for systems of ordinary differential equations (ODEs).We classify a class of fourth-order evolutionequations which admit certain higher-order generalized conditional symmetries (GCSs) and give some examples to showthe main reduction *** reductions cannot be derived within the framework of the standard lie approach,which hints that the technique presented here is something essential for the dimensional reduction of evolu tion equations.

关键词： fourth-order evolution equation generalized conditional symmetry Cauchy problem

Approximate Symmetry Reduction for Initial-value Problems of the Extended KdV-Burgers Equations with Perturbation

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Chinese Physics Letters 2011年第3期28卷 1-4页

作者： li ji-na ZHANG Shun-li Center for Nonlinear Studies Department of MathematicsNorthwest UniversityXi’an 710069 Center of Nonlinear Science Ningbo UniversityNingbo 315211

Approximate generalized conditional symmetry is developed to study the approximate symmetry reduction for initial-value problems of the extended KdV-Burgers equations with *** equations can be reduced to initial-value problems for some systems of first-order perturbed ordinary differential equations in terms of a new *** classification theorems are obtained and an example is taken to show the main reduction procedure.

关键词： perturbation. value symmetry

Cauchy Problems for KdV-type Equations and Higher-Order Conditional Symmetries

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Communications in Theoretical Physics 2008年第3期49卷 545-548页

作者： li ji-na ZHANG Shun-li ZUO Su-li Center for Nonlinear Studies Department of Mathematics Northwest University Xi＇an 710069 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

We develop the generalized conditional symmetry （GCS） approach to solve the problem of dimensional reduction of Cauchy problems for the KdV-type equations. We characterize these equations that admit certain higherorder GCSs and show the main reduction procedure by some examples. The obtained reductions cannot be derived within the framework of the standard lie approach.

关键词： KdV-type equations generalized conditional symmetry Cauchy problem

Symmetry Reduction of Initial-Value Problems for a Class of Third-order Evolution Equations

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Communications in Theoretical Physics 2009年第7期52卷 55-59页

作者： li ji-na FENG Wei QI Xin-Lei ZHANG Shun-li Center for Nonlinear Studies Department of Mathematics Northwest University Xi＇an 710069 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

Symmetry reduction of a class of third-order evolution equations that admit certain generalized conditionalsymmetries (GCSs) is *** reducibility of the initial-value problem for an evolution equation to a Cauchyproblem for a system of ordinary differential equations (ODEs) is characterized via the GCS and its lie *** classification theorems are obtained and some examples are taken to show the main reduction procedure.

关键词： symmetry reduction third-order evolution equation Cauchy problem

Structural Elucidation and HPLC Analysis of Six Flavone Glycosides from Artemisiafrigida Willd.

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Chemical Research in Chinese Universities 2013年第3期29卷 439-444页

作者： WANG Qing-hu AO Wu-li-ji DAI na-yin-tai College of Traditional Mongolian Medicine lnner Mongolia University for Nationalities Tongliao 028000 P. R. China

An investigation of the EtOAc-soluble fraction from the aerial parts ofArtemisiafrigida Willd.（A. frigida） led to the isolation of three new flavonoid glycosides together with three known compounds. Their structures were elucidated by spectral experiments. At the same time, high-performance liquid chromatographic（HPLC） method was used for the simultaneous determination of the six flavonoid glycosides from the aerial parts ofA. frigida. The separation by gradient elution was performed on a Hypersil ODS-2 column（250 mm×4.6 mm, 5 μm） at 30℃ with acetonitrile and water as the mobile phase, and monitored by absorbance at 276 nm. The parameters of linearity, precision, accuracy and specificity of the method were evaluated. The recovery of the method is 96.50%--98.01%, and linearity（r〉0.9992） was obtained for all the flavonoid glycosides. A high degree of specificity as well as repeatability and reproducibility（relative standard deviation values less than 2.0%） were also achieved. This assay was applied to the determination of six flavonoid glycosides in ten samples. The results indicate that the developed assay method was rapid, accurate, reliable and could be readily utilized as a quantitative analysis method for A. frigida.

关键词： Structural elucidation High-performance liquid chromatography simultaneous determination Flavonoid glycoside Artemisia frigida

A novel CLCN5 mutation in a Chinese boy with Dent's disease

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World Journal of Pediatrics 2014年第3期10卷 275-277页

作者： li-na ji Chao-Ying Chen jing-jing Wang li Cao Nephrology Department Children's Hospital Affi liated to Capital Institute of PediatricsNo 2 Yabao RoadChaoyang DistrictBeijing 100020China

Background:Dent's disease is a rare X-linked recessive hereditary disease caused by mutations in either the CLCN5 or OCRL1 *** disease is characterized by manifestations of proximal renal tubule dysfunction associated with low molecular weight proteinuria(LMWP),hypercalciuria,nephrocalcinosis,nephrolithiasis,and progressive renal ***:We report a Chinese boy with Dent's disease,clinically diagnosed by LMWP and *** analysis was made of the CLCN5 and OCRL1 *** studies were also ***:A splice site mutation IVS6,+2T>C of the CLCN5 gene was revealed in this case,and it was not reported ***:Clinical and genetic analysis is valuable for the diagnosis of Dent's disease.A novel mutation in the CLCN5 gene was identifi ed in our patient.

关键词： CLCN5 Dent's disease gene mutation hypercalciuria proteinuria

Selective laser melting of lanthanum oxide-reinforced tungsten composites:microstructure and mechanical properties

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Tungsten 2022年第1期4卷 67-78页

作者： Shen-Yu Wei li-na ji Wen-jie Wu Hong-lin Ma Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China Chongqing Key Laboratory of Additive Manufacturing Technology and Systems Chongqing 400714China

In this study,La_(2)O_(3)nanoparticles were introduced into the tungsten(W)matrix to optimize the microstructure and properties of pure *** W-La_(2)O_(3)composites with different mass ratios of La_(2)O_(3)were manufactured by selective laser melting(SLM).The result showed that the average grain sizes for W-1 wt%La_(2)O_(3)and W-2 wt%La_(2)O_(3)were reduced by more than 51.3%compared with that of pure W,and the defects obviously *** microhardness and compressive strength of the SLM W-2 wt%La_(2)O_(3)sample reached 455 HV and 2194 MPa,*** toughness of the SLM W-2 wt%La_(2)O_(3)sample also improved *** main reason was that the La_(2)O_(3)nanoparticles provide many heterogeneous nucleation sites to refine the *** other main reason was that La_(2)O_(3)nanoparticles formed into dislocation loops,which hindered the movement of dislocations and then increased the strength *** research provided a new method to improve the mechanical properties of SLM W by introducing La_(2)O_(3)nanoparticles to achieve fine-grains strengthening and Orowan strengthening.

关键词： Selective laser melting W-La_(2)O_(3)composites Cracks Mechanical properties

Clinical features of pediatric patients with COVID-19: a report of two family cluster cases

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World Journal of Pediatrics 2020年第3期16卷 267-270页

作者： li-na ji Shuang Chao Yue-jiao Wang Xue-Jun li Xiang-Dong Mu Ming-Gui lin Rong-Meng jiang Department of Pediatrics Beijing Tsinghua Changgung Hospital Affiliated To Tsinghua UniversityLitang Road No.168Changping DistrictBeijing 102218China Department of Respiratory Medicine Beijing Tsinghua Changgung Hospital Affiliated To Tsinghua UniversityLitang Road No.168Changping DistrictBeijing 102218China Department of Infectious Disease Beijing Tsinghua Changgung Hospital Affiliated To Tsinghua UniversityLitang Road No.168Changping DistrictBeijing 102218China Department of Infectious Disease Beijing Ditan Hospital Affiliated To Capital Medical UniversityJingshun East Street No.8Chaoyang DistrictBeijing 100011China

Background Coronovirus disease 2019 (COVID-19) has spread rapidly across the *** of all ages are susceptible to ***,literature reports on pediatric patients are *** To improve the recognition of COVID-19 infection in children,we retrospectively reviewed two confirmed pediatric cases from two family *** clinical features and laboratory examination results of the children and their family members were *** The two confirmed children only presented with mild respiratory or gastrointestinal *** of them had normal chest CT *** general and symptomatic treatments,both children recovered *** families had travel histories to Hubei *** Pediatric patients with COVID-19 are mostly owing to family cluster or with a close contact *** children have relatively milder clinical symptoms than infected *** should attach importance to early recognition,early diagnosis,and early treatment of infected children.

关键词： Children Coronavirus COVID-19 Wuhan