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71.
Bingbing Wang Hongming Lou Hongli Xu Junpeng Zhao Qiujun Wang Qiao Shi Yonghong Deng 《RSC advances》2018,8(12):6373
In this work, a novel star-comb copolymer based on poly(d,l-lactide) (PDLLA) macromonomer and poly(ethylene glycol)methyl ether methacrylate (PEGMA) was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries. The six-arm vinyl functionalized PDLLA macromonomer was synthesized by a ring-opening polymerization (ROP) of d,l-lactide and subsequently an acylation of the hydroxy end-groups. A series of free-standing solid polymer electrolyte membranes from different ratios of PDLLA, PEGMA and LiTFSI were prepared through solvent-free free radical polymerization under UV radiation. The chemical structure of the obtained polymers was confirmed by 1H NMR and FTIR. The as-prepared six-arm star-comb solid polymer electrolytes (PDLLA-SPEs) exhibit good thermal stability with Td5%s of ∼270 °C and low Tgs of −48 to −34 °C. The electrochemical characterization shows that the PDLLA-SPEs possess a wide electrochemical window up to 5.1 V with an optimal ionic conductivity of 9.7 × 10−5 S cm−1 at 60 °C at an EO/Li+ ratio of 16 : 1. Furthermore, the all-solid-state LiFePO4/Li cells display extraordinary cycling and rate performances at 60 °C by curing the PDLLA-SPEs directly on the cathode. These superior properties of the six-arm star-comb PDLLA-SPE make it a promising candidate solid electrolyte for lithium batteries.In this work, a novel star-comb copolymer based on PDLLA macromonomer and PEGMA was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries. 相似文献
72.
In recent years, perovskite solar cells (PSCs) have attracted great attention in the photovoltaic research field, because of their high-efficiency (certified 22.1%) and low-cost. In this review paper, we briefly introduce the history of efficiency development for PSCs, and discuss some of the major problems for large-area (≥1 cm2) PSC devices. In addition, we summarize the recent progress in the aspects of fabrication methods for large-area perovskite films, and improving the efficiency and stability of the large-area PSC devices. Finally, we give a short summary and outlook of large-area PSC devices. This article is mainly organized into three parts. The first part focuses on the main fabricating technologies for large-area perovskite films. The second section discusses some methods that are used to improve the efficiency of PSCs. In the last part, different approaches are used to improve the stability of PSCs.In this review, we summarize the recent progress in the aspects of the fabrication methods for large-area perovskite films, improving the efficiency and stability of the large-area PSC devices. 相似文献
73.
目的 了解新疆乌鲁木齐市居民甲状腺疾病知晓率及年龄分布的差异, 分析甲状腺功能、甲状腺自身抗体与尿碘相关性及其变化规律。方法 2013年5月采用横断面方法随机抽取乌鲁木齐市1 995名常住居民, 其中健康成年人1 906名, 年龄18~84岁, 平均(46.3±14.2)岁, 男性占30.4%, 女性占69.6%。采集一次性随机晨尿10 ml测定尿碘, 静脉血测定促甲状腺素(TSH)、血清游离甲状腺素(FT4)、游离三碘甲状腺原氨酸(FT3)、甲状腺球蛋白抗体(TgAb)、甲状腺过氧化物酶抗体(TPOAb)。结果 (1)调查居民中新诊断甲状腺功能异常者213例(11.2%, 其中女性占78.4%), 甲状腺功能亢进(甲亢)者占2.7%, 甲状腺功能减低(甲减)者占8.5%;TgAb阳性率为23.2%, TPOAb阳性率为16.6%;人群尿碘M=134.5 μg/L, 人群中碘缺乏占32%, 碘适宜占58%, 碘过量占10%;甲状腺功能正常组和异常组比较、抗体阳性组与阴性组比较其尿碘水平的差异均无统计学意义。(2)将人群划分18~、45~和≥60岁3个年龄组, 则显示随年龄增长TSH水平有明显差异, 且女性高于男性(P<0.001);甲状腺功能正常人群中, TSH水平为抗体阳性组明显高于阴性组(P<0.000 1)。(3)≥60岁与<60岁人群比较, 甲减患病率显著增加(P=0.008), 但甲亢患病率无明显差别, 抗体阳性率亦无明显差异。结论 乌鲁木齐市社区居民甲状腺功能、自身抗体与尿碘水平无明显相关, 女性甲状腺功能异常、抗体阳性率均高于男性, 抗体阳性组TSH水平明显高于阴性组, 老年人群甲减患病率显著增高, 应对该人群定期监测。 相似文献
74.
目的:比较紫杉醇脂质体和紫杉醇治疗晚期食管癌的安全性及临床疗效。方法将该科近3年收治的90例晚期食管癌患者分为2组。紫杉醇脂质体组(试验组)45例给予紫杉醇脂质体80 mg/m2静脉滴注,第1、8天;奈达铂75 mg/m2静脉滴注,第1天。紫杉醇组(对照组)45例给予紫杉醇80 mg/m2,静脉滴注,第1、8天;奈达铂75 mg/m2,静脉滴注,第1天。3周为1个周期,化疗2个周期后按WHO标准进行评估近期疗效及不良反应。结果近期疗效方面,紫杉醇脂质体和紫杉醇相比较,差异无统计学意义(P>0.05),但在紫杉醇溶媒产生的过敏反应方面,试验组明显低于对照组,差异有统计学意义(P<0.05)。结论紫杉醇脂质体或紫杉醇联合奈达铂治疗晚期食管癌疗效确切,两种紫杉醇疗效相当,但紫杉醇脂质体的过敏反应明显低于紫杉醇,值得临床推广。 相似文献
75.
目的对北京协和医院新生儿重症监护室(neonatal intensive care units,NICU)早产儿定植和感染部位、环境及益生菌中分离出的肠球菌进行菌种鉴定及同源性分析。方法收集2017年6月1—10日NICU及益生菌制剂中分离出的肠球菌共11株,用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)进行菌种鉴定,采用微量肉汤稀释法测定临床常用抗菌药物的最低抑菌浓度(MIC),用多位点序列分型(MLST)及脉冲场凝胶电泳(PFGE)进行菌株同源性分析。结果 11株菌均为粪肠球菌,对氨苄西林、万古霉素、替考拉宁、呋喃妥因、氯霉素、左氧氟沙星、利奈唑胺等抗菌药物均表现为敏感,仅1株菌对四环素和红霉素耐药。11株粪肠球菌经PFGE分为a-d 4个克隆群,MLST分型分别为ST624、ST25、ST40及ST16,PFGE与MLST分型结果一致。结论此次NICU早产儿粪肠球菌定植或感染可能与益生菌制剂的使用及物表定植的粪肠球菌相关。 相似文献
76.
目的分析生活饮用水和水源水中草甘膦的污染现状,以便对河南省生活饮用水和水源水中草甘膦的污染情况进行初步了解。方法用Fisher精确检验和非参数Wilcoxon秩和检验对检测结果进行统计学分析。结果利用Fisher精确检验(P=0.7540、P=0.7079)和非参数Wilcoxon秩和检验(Z=1.2143,P=0.2246)对水源水中检出草甘膦的样品进行统计分析,其检出率和含量结果无统计学意义,利用Fisher精确检验对三地区被检查的样品进行统计学分析,其不同地区间检出样品差异有统计学意义(P0.0001)。结论尽管生活饮用水均未检出草甘膦,考虑到草甘膦是一种高效低毒和广泛使用的除草剂,仍需加强对生活饮用水中草甘膦的检测。 相似文献
77.
Wu Nan Shao Yuming Huo Jianwei Zhang Yanan Cao Yihan Jing Hongli Zhang Fa Yu Chenyang Yu Yanying Li Chen Song Hongmei Zhang Wen 《Clinical rheumatology》2021,40(4):1487-1495
Clinical Rheumatology - Pediatric SAPHO syndrome is regarded as the equivalent of chronic recurrent multifocal osteomyelitis or chronic non-bacterial osteomyelitis. This study aimed to evaluate the... 相似文献
78.
Yuhui Cheng Lin Jiao Weixiu Li Jialing Wang Zhangyu Lin Hongli Lai Binwu Ying 《Journal of clinical laboratory analysis》2021,35(2)
BackgroundThe role of collagen type XVIII alpha 1 chain (COL18A1) in anti‐tuberculosis drug‐induced hepatotoxicity (ATDH) has not been reported. This study aimed to explore the association between of COL18A1 variants and ATDH susceptibility.MethodsA total of 746 patients were enrolled in our study from December 2016 to April 2018, and all subjects in the study signed an informed consent form. The custom‐by‐design 2x48‐Plex SNPscanTM kit was used to genotype all selected 11 SNPs. Categorical variables were compared by chi‐square (χ2) or Fisher''s exact test, while continuous variables were compared by Mann‐Whitney''s U test. Plink was utilized to analyze allelic and genotypic frequencies, and genetic models. Multivariate logistic regression analyses were used to adjust potential factors. The odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were also calculated.ResultsAmong patients with successfully genotyping, there were 114 cases and 612 controls. The mutant A allele of rs12483377 conferred the decreased risk of ATDH (OR = 0.13, 95%CI: 0.02–0.98, P = 0.020), and this significance still existed after adjusting age and gender (P = 0.024). The mutant homozygote AA genotype of rs12483377 was associated with decreased total protein levels (P = 0.018).ConclusionOur study first revealed that the A allele of COL18A1 rs12483377 was associated with the decreased risk of ATDH in the Western Chinese Han population, providing new perspective for the molecular prediction, precise diagnosis, and individual treatment of ATDH. 相似文献
79.
目的 探讨血清食物特异性IgG抗体检测在过敏性鼻炎中的临床意义.方法 采用酶联免疫吸附法检测1067例过敏性鼻炎患者血清14种食物特异性IgG抗体水平.结果 食物特异性IgG抗体阳性率为77.51%,其中单阳性的占32.53%,多重阳性的占67.47%;食物不耐受的程度,以轻度不耐受最为多见(61.62%),中度和重度不耐受分别占22.88%和15.51%,中、重度不耐受多见于鸡蛋、牛奶和小麦;检测阳性率从高到低依次为:鸡蛋(56.14%)、牛奶(28.40%)、小麦(20.43%)、西红柿(14.81%)、大米(13.12%)、大豆(11.90%)、鳕鱼(9.93%)、螃蟹(7.87%)、玉米(6.56%)、河虾(5.90%)、蘑菇(4.03%)、鸡肉(3.47%)、猪肉(2.44%)、牛肉(0.56%);阳性率较高的鸡蛋、牛奶、小麦、西红柿、大米在≤14岁患者组阳性率最高,随年龄增长而呈下降趋势.结论 过敏性鼻炎患者食物不耐受的发生率较高,血清食物特异性IgG检测可用于筛查不耐受食物. 相似文献
80.
Inflammation - Neonatal sepsis (NS) is a severe syndrome in newborns that is induced by infections, and the initiation and development of NS are closely associated with the function of miRs. In the... 相似文献