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Synthesis and electromagnetic wave absorption properties of Gd-Co ferrite@carbon core-shell structure composites

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Rare Metals 2023年第1期42卷 254-262页

作者： Jing Gao Zhi-Jun Ma fu-li liu Xing-Yuan Weng School of Mining Liaoning Technical UniversityFuxin123000China

Developing high-performance electromagnetic absorbing materials remains a *** this work,Gd-Co ferrite@carbon core-shell structure composites were synthesized by a two-step hydrothermal *** effects of rare earth Gd doping amount on the microstructure and electromagnetic wave absorption properties of cobalt ferrite@carbon composites were mainly *** results show that an appropriate amount of Gd doping can refine the crystal grain size of cobalt ferrite@carbon ***,when the doping amount of Gd exceeds the solid solubility threshold,the secondary phase GdFeO_(3)will be generated and the grain size will *** the doping amount of Gd is x=0.04,the reflection loss(RL) of the CoFe_(1.96)Gd_(0.04)O_(4)@C composites reaches the minimum value of -9.26 dB at the absorption layer thickness of 2.0 mm and a frequency of 13.67 GHz,and the effective absorption band(EAB) is 5.01 GHz(10.95-15.96 GHz).Compared with the CoFe_(2)O_(4)@C composites,the RL of the CoFe_(1.96)Gd_(0.04)O_(4)@C composites is increased by 79.35%,and the EAB is broadened by 3.51%.Gd ions enhance the dielectric loss through the grain size effect,and the increase of magnetocrystalline anisotropy enhances the magnetic *** CoFe_(1.96)Gd_(0.04)O_(4)@C composites have excellent impedance matching,which relies on the strong magnetic loss of ferrite,the interface polarization,and dipole polarization formed by the carbon shell to attenuate electromagnetic waves.

关键词： Rare earth Gd Cobalt ferrite Core-shell structure composites Electromagnetic wave absorption

Facile Synthesis and Adsorption Properties of Phosphonated Cellulose Beads for Selective Removal of Low-density lipoprotein

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Chinese Chemical Letters 2006年第9期17卷 1193-1196页

作者： Hao Feng YU Guo Qi fu li liu Bing lin HE The Key Laboratory of functional Polymer Materials of Ministry of Education Institute of Polymer Chemistry Nankai University Tianjin 300071

A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective removal of low-density lipoprotein from human plasma. The effects of preparation conditions on the lipoprotein sorption properties of the resulted adsorbent were investigated. The adsorption dynamics was also examined.

关键词： Cellulose beads phosphonation low-density lipoprotein adsorption hyperlipemia

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

Comparison of modified percutaneous transhepatic variceal embolization and endoscopic cyanoacrylate injection for gastric variceal rebleeding

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World Journal of Gastroenterology 2013年第5期19卷 706-714页

作者： Jing Wang Xiang-Guo Tian Yan li Chun-Qing Zhang fu-li liu Yi Cui Ji-Yong liu Department of Gastroenterology Provincial Hospital Affiliated to Shandong University

AIM:To compare the efficacy of modified percutaneous transhepatic variceal embolization(PTVE)with 2-octyl-cyanoacrylate(2-OCA)and endoscopic variceal obturation(EVO)with an injection of 2-OCA for prophylaxis of gastric variceal rebleeding. METHODS:In this retrospective study,the medical records of liver cirrhosis patients with gastric variceal bleeding who underwent either endoscopic 2-OCA(EVO) or modified PTVE using 2-OCA at Shandong Provincial Hospital from January 2006 to December 2008 were *** demographics,rebleeding rate,survival rate,and complications were compared between the two groups(PTVE and EVO).All results were expressed as mean±SD,or as a *** variables were compared by two sample Student t tests, and qualitative variables were compared by the Fisher exact test or theχ 2 test(with Yates correction)where appropriate.A P value less than 0.05 was considered *** computation was performed using SPSS 13.0 software. RESULTS:A total of 77 patients were included;45 patients who underwent EVO and 32 patients who received *** the follow-up(19.78±7.70 mo in the EVO group,vs 21.53±8.56 mo in the PTVE group) rebleeding occurred in 17 patients in the EVO group and in 4 patients in the PTVE group(37.78%vs 12.5%, P=0.028).The cumulative rebleeding-free rate was 75%,59%,and 49%in 1,2,and 3 years respectively for EVO,and 93%,84%,and 84%for PTVE(P=0.011). Cox analysis was used to identify independent factors that predicted rebleeding after *** including age,gender,cause,Child-Pugh classification, size of gastric varices(GV),location of GV,and treatment methods were *** was revealed that Child-Pugh classification[risk ratio(RR)2.10,95%CI:1.03-4.28,P=0.040],choice of treatment(RR 0.25, 95%CI:0.08-0.80,P=0.019),and size of GV(RR 2.14, 95%CI:1.07-4.28,P=0.032)were the independent factors for predicting ***-up computed tomography revealed that cyanoacrylate was retained in the var

关键词： Gastric varices Endoscopic variceal obturation Percutaneous transhepatic variceal embolization 2-octyl-cyanoacrylate Bleeding

Isolation and Purification of Myxobacteria in Chengdu

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Animal Husbandry and Feed Science 2011年第1期3卷 25-27页

作者： liu Bing-hua YANG lin FENG li-fu HE liu-xing School of Medicine and Nurse Chengdu University Chengdu 610015 China

[ Objective] To lay the basis for further studying bioactive substances in myxobacteria. [ Method] A total of 35 samples including fresh water, mud, rabbit dung, sheep dung, weathered rock and rotten wood were collected from districts and counties of Chengdu. After pretreatment, the myxobacteria were isolated and purified using different methods. Vegetative cells, myxospores, fruiting body and colony morphology of these myxobacteria strains were observed. E ResultJ Forty-two myxobacteda strains were isolated and purified. They were classified into seven genera including Myxococcus, Angiococcus, Chondromyces, Sorangium, Melittangium, Stigmatella and Archangium. The plating efficiency of myxobacteria was highest in the fresh water samples. [ Conclusion] Abundant myxobacteria resource is found in fresh water.

关键词： Myxobacteria Isolation Purification Strains

Molecular marker for rapid detection of Aleurodicus disperses(Homoptera:Aleyrodidae)

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Molecular marker for rapid detection of Aleurodicus disperse...

A New Synthetic Route to the Synthesis of Some Insect Sex Pheromones Analogs

第三届全国生物入侵大会

作者： Wei-Dong li~*,fu-Xiu liu,Xiang-Shan Feng Hainan Entry-Exit Inspection and Quarantine Bureau,Haikou 570311,China

The spiralling whitefly,Aleurodicus disperses Russell,is a invasive pest worldwide. Morphological identification of the pest is very difficult due to the small size and high degree similarity with other *** this study,the method for rapid detection of *** was established based on CO I gene sequence,one pair of primers which are specific to spiralling whitefly was *** fragment amplified by the primers was 399 bp in *** tests performed with this pair of primers showed that all specimens of *** were *** this method was tested on a single male and female adult,a single nymph(1st to 4th instar),even a single egg,,and proved to be applicable for these stages of *** ***,When the dilution was 1/4000 of a whole female adult of ***,the 399 bp DNA fragment could be identified for all *** establishment of the method for rapid detection of *** provided a technical support in prevention spread of the spiralling whitefly in China and in reduction of its harmfulness.

关键词： Aleurodicus disperses Molecular marker Rapid detection

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A New Synthetic Route to the Synthesis of Some Insect Sex Ph...

利用GPS轨迹二次聚类方法进行道路拥堵精细化识别

The First Asia—Pacific Conference on Chemical Ecology

作者： Jun lin Rong Xu Hong-You Zhu Yan-Wu li Quan li and fu-Chu liu Department of Chemistry Yunnan University Kunming.650091.China

＜正＞The sex pheromones of Lepidoptera are usually unsaturated straight-chain alcohols,acetates,aldehydes, or *** of their biological importance,more and more new methods have been incorporated to synthesize these sex *** on the decarbonylation reactions of carboxylic acid with dichlorobis （triphenylphosphine） palladium catalyst system to terminal olefines and the reaction of reduction of olefines to primary alcohols with calcium boronhydride,we report here a new and convenient route to synthesize a variety of Lepidoptera sex pheromones analogs.

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武汉大学学报（信息科学版） 2017年第9期42卷 1264-1270页

作者：付子圣李秋萍柳林周素红中山大学地理科学与规划学院综合地理信息研究中心广东广州510275 广东省城市化与地理环境空间模拟重点实验室广东广州510275 辛辛那提大学地理系美国俄亥俄州452210131

针对当前在精细识别道路拥堵时空范围方面研究的不足,提出一种利用GPS轨迹的二次聚类方法,通过快速识别大批量在时间、空间上差异较小且速度相近的轨迹段,反映出道路交通状态及时空变化趋势,并根据速度阈值确定拥堵状态及精细时空范围... 详细信息

针对当前在精细识别道路拥堵时空范围方面研究的不足,提出一种利用GPS轨迹的二次聚类方法,通过快速识别大批量在时间、空间上差异较小且速度相近的轨迹段,反映出道路交通状态及时空变化趋势,并根据速度阈值确定拥堵状态及精细时空范围。首先将轨迹按采样间隔划分成若干条子轨迹,针对子轨迹段提出相似队列的概念,并设计了基于密度的空间聚类的相似队列提取方法,通过初次聚类合并相似子轨迹段,再利用改进的欧氏空间相似度度量函数计算相似队列间的时空距离,最后以相似队列为基本单元,基于模糊C均值聚类的方法进行二次聚类,根据聚类的结果进行交通流状态的识别和划分。以广州市主干路真实出租车GPS轨迹数据为例,对该方法进行验证。实验结果表明,该二次聚类方法能够较为精细地反映城市道路的拥堵时空范围,便于管理者精准疏散城市道路拥堵,相比直接聚类方法可以有效提升大批量轨迹数据的计算效率。

关键词：道路拥堵精细识别时空轨迹聚类相似队列轨迹相似性度量

基于线粒体16SrRNA基因序列的长江下游重要水体脆弱象鼻溞群体遗传结构分析

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淡水渔业 2017年第3期47卷 3-8,24页

作者：崔光艳付立霞王柳富魏文志扬州大学动物科学与技术学院江苏扬州225009

为了解长江下游地区10个水体脆弱象鼻溞群体的遗传结构,研究测定了脆弱象鼻溞(Bosmina fatalis)线粒体16SrRNA基因序列,结果显示,100个样本中共有8个变异位点,定义了9个单倍型,单倍型多样性(Hd=0.284)和核苷酸多样性(Nd=0.000 76)均较低... 详细信息

为了解长江下游地区10个水体脆弱象鼻溞群体的遗传结构,研究测定了脆弱象鼻溞(Bosmina fatalis)线粒体16SrRNA基因序列,结果显示,100个样本中共有8个变异位点,定义了9个单倍型,单倍型多样性(Hd=0.284)和核苷酸多样性(Nd=0.000 76)均较低。AMOVA分子变异分析结果表明,脆弱象鼻溞遗传分化主要来自群体内,占93.33%,群体间的变异低,占6.67%。Fst值统计检验表明,各水体之间遗传分化不显著。系统发育树和中介网络图说明脆弱象鼻溞单倍型间关系较近,未形成明显谱系地理格局。中性检验和错配分布结果说明脆弱象鼻溞出现过群体扩张现象。

关键词：脆弱象鼻溞(Bosmina fatalis) 长江下游 16SrRNA 群体遗传结构