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Modification and refinement effects of Sb and Sr on Mg_(17)Al_(12) and Mg_2Si phases in Mg-12Al-0.7Si alloy

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China Foundry 2016年第5期13卷 310-315页

作者： Zhi-wen wang hong-xia wang Jia-lin Gong Ming Li Wei-li Cheng Wei Liang Key Laboratory of lnterface Science and Engineering in Advanced Materials Taiyuan University of Technology Ministry of Education Taiyuan 030024 Shanxi China

The effects of Sb and Sr on the modification and refinement of Mg17Al12 and Mg2Si phases in Mg- 12Al-0.7Si alloy were investigated and compared. The microstructure and mechanical properties of Mg-12Al0.7Si alloy and its modification mechanism by Sb and Sr were investigated using a scanning electron microscope （SEM）, an energy dispersive spectrometer （EDS）, X-ray diffraction （XRD） and differential thermal analysis （DTA）. The results indicate that by adding 0.5wt.% Sb to the Mg-12Al-0.7Si alloy, the Mg17Al12 phase was refined and broken into some discontinuous island structures. However, some network Mg17Al12 phases still can be detected in Mg-12Al-0.7Si-0.09Sr alloy. Therefore, Sb performs better in modification and refinement of Mg17Al12 phase than does Sr. Small amounts of fine polygonal shaped Mg2Si phases were found in Mg-12AI-0.7Si-0.5Sb alloy, while the morphology of Mg2Si phases in Mg-12Al-0.7Si-0.09Sr alloy changed from the coarse Chinese script shapes to fine granule and irregular polygonal shapes, indicating that the effects of modification and refinement on Mg2Si phase are more significant by adding 0.09wt.% Sr than 0.5wt.% Sb. The ultimate tensile strengths of the Sb and Sr modified Mg-12Al-0.7Si alloys were considerably increased both at room temperature and at 200 ℃.

关键词： magnesium alloy Sb Sr Mg17Al12 phase Mg2Si phase

Cistanche deserticola decoction alleviates the testicular toxicity induced by hydroxyurea in male mice

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Asian Journal of Andrology 2013年第6期15卷 838-840,I0011页

作者： Li Gu Wen-Ting Xiong Chao wang hong-xia Sun Guo-Fu Li Xin Liu Food and Health Engineering Research Center of State Education Ministry Sun Yat-Sen University Guangzhou 510275 China

This study aimed to evaluate testicular toxicity induced by hydroxyurea （HU） and the possible counteracting effect of an aqueous extract of Cistanche deserticola （CD）. HU is an antineoplastic drug that has potential reproductive toxicity, and Herba Cistanche has been used as a tonic for the reproductive system for thousands of years. Sixty mice were randomly divided into five groups. Except mice in normal group, the rest received HU （400 mg kg^-1 body weight） intragastrically. Meanwhile, mice in normal and HU control groups received purified water, and the rest received intragastrically three doses of CD decoctions （1.5, 3.0 and 6.0 g crude drug kg^-1 body weight, respectively） daily for 4 weeks. Severe testes lesions were observed, testes weight （P〈0.01） and serum luteinising hormone levels （P〈0.0 1） were also decreased significantly, in the HU groups. Three doses of CD decoctions alleviated the spermatogenetic cell degeneration induced by HU and modulated the serum sex hormones levels to some extent.

关键词： Cistanche deserticola hormones hydroxyurea semin iferous tubule

Finite Horizon H∞ Preview Control

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自动化学报 2010年第2期36卷 327-331页

The paper focuses on the H∞ preview control problem in the finite horizon. Starting with the traditional idea, we found the sticking point and used a suitable linear transformation to eliminate it. Finally, we obtained a sufficient and necessary condition and a simple control-law for the problem. Furthermore, a numerical example is also provided to illustrate that the controller can effectively improve the closed-loop performance.

关键词： H∞ 控制控制理论系统工程稳定性

Synthesis, Crystal Structure and Luminescence of One-dimensional Homochiral Terbium (Ⅲ) Coordination Polymers

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Chinese Journal of Structural Chemistry 2020年第6期39卷 1044-1050页

作者： XU Yan LI Xin-Xing wang hong-xia LIU Hao-Ran CHEN Meng-Qi DOU Qiang Department of Materials Science and Engineering Suqian CollegeSuqian 223800China Industrial Research Institute Suqian CollegeSuqian 223800China

Enantiomerically pure lanthanide(Ⅲ)-based phosphonates are successfully synthesized by using(R)-or(S)-(1-phenylethylamino)-methylphosphonate acid(pempH2),namely,R-or S-[Tb3(pempH2)2(pempH)7]-Cl2·H2O(R-Tb or S-Tb),crystallizing in chiral space group *** R-Tb shows a one-dimensional homochiral triple-stranded helical chain structure where the Tb(III)atoms are bridged by O-P-O units andμ3-O(P)*** thermal analysis,photoluminescence as well as optically active properties of compounds R-Tb and S-Tb have also been investigated.

关键词： terbium(Ⅲ) crystal structure luminescence homochiral

Differences Between Chinese and Western Cultures Perceived in Wedding Customs

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海外英语 2015年第24期 167-168,174页

作者：李嘉贤 wang hong-xia Baotou Vocational and Technical College of Inner Mongolia Inner Mongolia University of Science and Technology

The marriage customs and rites of wedding ceremony are different from country to country. By analyzing the differences of wedding ceremony between Chinese and Westerners, a conclusion will be made: different wedding customs reflect the differences between the Chinese culture and the western culture and different attitudes towards value and marriage of the Chinese and the western people. This paper aims at making the Chinese and the western people understand each other's culture and values well.

关键词： wedding customs Chinese and Western culture differences attitude towards value attitude towards marr

Mutation Analysis of MR-1, SLC2A 1, and CLCN1 in 28 PRRT2-negative Paroxysmal Kinesigenic Dyskinesia Patients

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Chinese Medical Journal 2016年第9期129卷 1017-1021页

作者： hong-xia wang hong-Fu Li Gong-Lu Liu xiao-Dan Wen Zhi-Ying Wu Department of Neurology and Institute of Neurology Huashan Hospital Shanghai Medical College Fudan University Shanghai 200040 China Department of Neurology and Research Center of Neurology in Second Affiliated Hospital The Collaborative Innovation center for Brain Science Zhejiang University School of Medicine Hangzhou Zhejiang 310009 China

Background： Paroxysmal kinesigenic dyskinesia （PKD） is the most common subtype of paroxysmal dyskinesias and is caused by mutations in PRRT2 gene. The majority of familial PKD was identified to harbor PRRT2 mutations. However, over two-third of sporadic PKD patients did not carry anyPRRT2 mutation, suggesting an existence of additional genetic mutations or possible misdiagnosis due to clinical overlap. Methods： A cohort of 28 Chinese patients clinically diagnosed with sporadic PKD and excluded PRRT2 mutations were recruited, Clinical features were evaluated, and all subjects were screened for MR-l, SLC2A1, and CLCN1 genes, which are the causative genes of paroxysmal nonkinesigenic dyskinesia （PNKD）, paroxysmal exertion-induced dyskinesia, and myotonia congenita （MC）, respectively, In addition, 200 genetically matched healthy individuals were recruited as controls. Results： A total of 16 genetic variants including 4 in MR-1 gene, 8 in SLC2A1 gene, and 4 in CLCN1 gene were detected. Among them, SLC2A1 c.363G〉A mutation was detected in one case, and CLCN1 c. 1205C〉T mutation was detected in other two cases. Neither of them was found in 200 controls as well as 1000 Genomes database and ExAC database. Both mutations were predicted to be pathogenic by SIFT and PolyPhen2. The SLC2A 1 c.363G〉A mutation was novel. Conclusions： The phenotypic overlap may lead to the difficulty in distinguishing PKD from PNKD and MC. For those PRRT2-negative PKD cases, screening of SLC2A1 and CLCN1 genes are useful in confirming the diagnosis.

关键词： CLCN I MR-l Paroxysmal Kinesigenic Dyskinesia PRRT2 SLC2A1

聚(二甘氨酸乙酯)磷腈的合成及其生物相容性

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高等学校化学学报 2007年第10期28卷 1984-1989页

作者：王洪霞高长有浙江大学高分子科学与工程学系教育部高分子合成与功能构造重点实验室杭州310027

氨基酸酯基取代的聚磷腈由于具有优良的水解性能并能降解成无毒产物,因而成为一类非常有吸引力的生物医用材料.采用两步法合成了聚(二甘氨酸乙酯)磷腈(PEGP).首先采用开环聚合的方法制备中间体聚二氯磷腈,再利用亲核取代方法合成PEGP.... 详细信息

氨基酸酯基取代的聚磷腈由于具有优良的水解性能并能降解成无毒产物,因而成为一类非常有吸引力的生物医用材料.采用两步法合成了聚(二甘氨酸乙酯)磷腈(PEGP).首先采用开环聚合的方法制备中间体聚二氯磷腈,再利用亲核取代方法合成PEGP.通过红外光谱、核磁共振及元素分析等确证了产物的结构.用蒸汽压下降法测得PEGP的分子量为12959,用DSC法测得其玻璃化转变温度为-21.5℃.采用体外细胞培养的方法评价了肝癌细胞HepG2和人工合成纤维细胞在PEGP薄膜表面的生长性能.结果表明,该材料不但没有细胞毒性,反而具有良好的促进细胞生长的能力,显示聚(二甘氨酸乙酯)磷腈在组织工程和再生医学中的潜在应用价值.

关键词：甘氨酸乙酯聚磷腈生物医用材料生物相容性

A New Construction Method for the Dual Tree Complex Wavelet Based on Direction Sensitivity

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自动化学报 2006年第1期32卷 47-53页

作者： wang hong-xia CHEN Bo CHENG Li-Zhi Department of Mathematics ＆ System Science National University of Defense Technology Changsha 410073

The conception of 'main direction' of multi-dimensional wavelet is established in this paper, and the capabilities of several classical complex wavelets for representing directional singularities are investigated based on their main directions. It is proved to be impossible to represent directional singularities optimally by a multi-resolution analysis (MRA) of L2(R2). Based on the above results, a new algorithm to construct Q-shift dual tree complex wavelet is proposed. By optimizing the main direction of parameterized wavelet filters, the difficulty in choosing stop-band frequency is overcome and the performances of the designed wavelet are improved too. Furthermore, results of image enhancement by various multi-scale methods are given, which show that the new designed Q-shift complex wavelet do offer significant improvement over the conventionally used wavelets. Direction sensitivity is an important index to the performance of 2D wavelets.

关键词：复合微波对偶树图象增加灵敏性

Semantic Web Enabled the Context Information in Ubiquitous Computing System

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通讯和计算机（中英文版） 2005年第5期2卷 20-26页

作者： Xuhui Chen Yimin wang xiangling xia hong Jiang School of Computer and Communication Lanzhou University of Technology Lanzhou Gansu 730050 China