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耐高温聚合物微/纳米纤维制备技术及应用研究进展 被引量:3
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作者 李好义 陈琪琪 +4 位作者 刘宇健 李相男 陈晓青 杨涛 杨卫民 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第12期158-164,共7页
耐高温聚合物微/纳米纤维由于高温下仍保持良好的力学性能和热稳定性,并具备高孔隙率、高比表面积等优异特性,因而在高温过滤吸附、电池隔膜以及高温催化等领域应用前景广阔。文中重点介绍了国内外制备聚苯硫醚(PPS)、聚醚醚酮(PEEK)、... 耐高温聚合物微/纳米纤维由于高温下仍保持良好的力学性能和热稳定性,并具备高孔隙率、高比表面积等优异特性,因而在高温过滤吸附、电池隔膜以及高温催化等领域应用前景广阔。文中重点介绍了国内外制备聚苯硫醚(PPS)、聚醚醚酮(PEEK)、聚四氟乙烯(PTFE)、聚砜类(PSF和PES)和聚酰亚胺(PI)微/纳米纤维的最新技术及应用进展,最后对耐高温微/纳米纤维未来的发展趋势进行了展望,以期为高性能耐高温聚合物微/纳米纤维的制备和应用研究提供新的思路。 展开更多
关键词 耐高温 纳米纤维 静电纺丝 纳米结构 过滤
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Distributional dynamic and trend evolution of China's agricultural carbon emissions-an analysis on panel data of 31 provinces from 2002 to 2011 被引量:6
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作者 Yun Tian Junbiao Zhang qiqi chen 《Chinese Journal of Population,Resources and Environment》 2015年第3期206-214,共9页
Researching the dynamic distribution characteristics and trend evolution of agricultural carbon emissions is of considerable significance in formulating an effective agricultural carbon reduction policy.Based on measu... Researching the dynamic distribution characteristics and trend evolution of agricultural carbon emissions is of considerable significance in formulating an effective agricultural carbon reduction policy.Based on measurement of agricultural carbon emissions of 31 provinces over the period 2002-2011,the study observed regional differences and the dynamic evolution of distribution of agricultural carbon emissions using agricultural carbon intensity as the indicator,accompanied by Gini coefficients and the kernel density estimation method.The results demonstrate first that agricultural carbon emissions for China show an obvious nonequilibrium nature in regard to spatial distribution.According to the differences in agricultural carbon emissions dynamic trends,we divided the 31 regions into four types- continuous decline,fluctuating decline,continuous increase,and fluctuating increase.Further,agricultural carbon emissions intensity showed a downward trend with significant differences in the research areas.Second,the gap in spatial distribution of national agricultural carbon emissions is gradually expanding based on the results calculated by Gini coefficient.From the perception of regional differences in agricultural carbon emissions,the eastern region showed an average level,the gap was more obvious in the central region,while western region showed a trend of fluctuating downward.Third,according to estimation by kernel density,the regional disparity in agricultural carbon emissions had a downward,but limited,trend.In regard to agricultural carbon emissions over the three areas,the regional gap not only tended to decrease but also showed a "four way" differentiation phenomenon in the eastern region.The difference in the central region difference was narrower.On the whole,the gap for the western region reduced steadily over a small range. 展开更多
关键词 China agricultural carbon emissions distributional DYNAMIC TREND EVOLUTION KERNEL density
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Cloning And Characterization Of A Geranylgeranyl Diphosphate Synthase Gene From Taxus Chinensis
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作者 Junhao Shen Yangyang Qiao +5 位作者 Yongqin chen Jungui Dai qiqi chen Zhifan Yang Xuzhi Ruan Ronghua Wei 《生物工程前沿(中英文版)》 2016年第1期11-21,共11页
Taxol(Paclitaxel)is a diterpene from Taxus species and has been used in treatment of various kinds of cancers.Geranylgeranyl diphosphate synthase(GGPPS)catalyzes the formation of geranylgeranyl diphosphate(GGPP,the co... Taxol(Paclitaxel)is a diterpene from Taxus species and has been used in treatment of various kinds of cancers.Geranylgeranyl diphosphate synthase(GGPPS)catalyzes the formation of geranylgeranyl diphosphate(GGPP,the common precursor for diterpenes and plays a key role in taxol biosynthesis.Here we report a functional GGPPS gene from Taxus chinensis(designated TcGGPPS).TcGGPPS is an intron free gene and has a 1,182-bp open reading frame encoding a polypeptide of 393 amino acid residues with a calculated molecular mass of 42.63 kDa and an isoelectric point of 5.58.The catalytic activity of TcGGPPS for production of GGPP was verified by a color enhancement assay in the Escherichia coli cells harboring plasmid pAC-BETA.Multiple sequence alignment indicates that TcGGPPS is a little different in sequence from the functional GGPPS genes from other Taxus species such as T.canadensis,T.media and T.wallichiana,which are almost identical to each other.Protein structure prediction by using bioinformatics reveals that TcGGPPS consists of 52.2%α-helix,10.9%extended strand,8.4%β-turn and 28.5%random coil,and has a three-dimensional structure highly similar to the structurally known Sinapis alba GGPPS.In silicon predictions also demonstrate that TcGGPPS has a plastid-targeting peptide at the N-terminus,suggesting it is responsible for the synthesis of GGPP in plastids. 展开更多
关键词 TAXUS CHINENSIS Geranylgeranyl DIPHOSPHATE SYNTHASE Gene CLONING TAXOL Biosynthesis
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Comparative Analysis of the Therapeutic Effect of Disinfectant and Non-disinfectant on the Separation of the Labia Minora in Infants
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作者 qiqi chen Guangyan Lin +1 位作者 Jun Xiong Ping Wei 《Journal of Clinical and Nursing Research》 2021年第6期159-165,共7页
Objective:To compare the effects of the use and non-use of a disinfectant on the outcomes of separation of the labia minora in infants.Methods:The patients were randomly divided into an experimental group with 24 case... Objective:To compare the effects of the use and non-use of a disinfectant on the outcomes of separation of the labia minora in infants.Methods:The patients were randomly divided into an experimental group with 24 cases and a control group with 25 cases.In the control group,1%iodophor was used to clean and disinfect the large and small labia and the surrounding skin,while normal saline was used in the experimental group.Other procedures such as the surgery and nursing method were the same in both groups.Results:There were no symptoms of urinary tract infection such as redness of the vulva,swelling,pain,and abnormal urination in the test group and control group after three days of follow-up,and no recurrence was seen at one month of follow-up.There was no statistically significant difference between the two groups(P>0.05).Conclusion:Use or non-use of a disinfectant to clean the urethral opening before separation of the labia minora has no significant effect on the outcomes,and does not cause postoperative urinary tract infection symptoms.Moreover,non-use of a disinfectant can prevent local irritation and reduce the economic burden on the patients. 展开更多
关键词 Labial adhesion DISINFECTANT Non-disinfectant
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可溶性程序性死亡受体-1及其配体和干扰素-γ在急性冠脉综合症患者血清中的表达特征和临床意义
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作者 牛红霞 毛月然 +5 位作者 陈琦琪 胥俊越 董静 王振 杨彦娜 张明 《中华卫生应急电子杂志》 2024年第1期10-15,共6页
目的对急性冠脉综合征患者血清中sPD-1/L1和干扰素-γ的表达特征及临床意义初步探讨。方法本研究回顾性纳入2020年11月至2022年10月北京电力医院急诊科收治的73例患者,将所有患者分为对照组和冠心病组(分为慢性冠脉疾病组和急性冠脉综... 目的对急性冠脉综合征患者血清中sPD-1/L1和干扰素-γ的表达特征及临床意义初步探讨。方法本研究回顾性纳入2020年11月至2022年10月北京电力医院急诊科收治的73例患者,将所有患者分为对照组和冠心病组(分为慢性冠脉疾病组和急性冠脉综合征组)。急性冠状动脉综合征组患者32例,其中男性19例,女性13例;年龄54~84岁,平均(69.09±14.97)岁。慢性冠脉疾病组患者21例,其中男性8例,女性13例;年龄65~83岁,平均(74.24±8.60)岁。对照组20例,其中男性13例,女性7例;年龄58~73岁,平均(65.70±7.39)岁,采用酶联免疫吸附试验法(ELISA)检测3组患者血清sPD-1及sPD-L1、IFN-γ水平。结果3组患者间血清免疫标志物对比分析可知,IL-18、IFN-γ、sPD-1/L1水平比较,差异有统计学意义(P<0.05),ACS组及慢性冠脉疾病组患者IL-18表达水平显著高于对照组,差异有统计学意义(P<0.01);慢性冠脉疾病组患者IFN-γ表达水平显著高于ACS组及对照组(P<0.05);sPD-1/L1在ACS组和慢性冠脉疾病组患者表达显著高于对照组人群,差异有统计学意义(P<0.05)。Pearson相关分析结果显示,ACS组患者血清IFN-γ表达与sPD-1(r=0.922,P<0.01)及L1(r=0.922,P<0.01)呈正相关。结论ACS患者中sPD-1/L1与IFN-γ之间存在一定的关系,ACS患者IFN-γ的释放增加,进而可能导致sPD-1/L1的表达增加,而sPD-1/L1表达的增加可能在ACS的免疫调节中发挥重要作用。 展开更多
关键词 急性冠脉综合征 可溶性程序性死亡受体-1 可溶性程序性死亡配体-1 干扰素-Γ
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Interfacial Modification,Electrode/Solid‑Electrolyte Engineering,and Monolithic Construction of Solid‑State Batteries
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作者 Qirong Liu qiqi chen +1 位作者 Yongbing Tang Hui‑Ming cheng 《Electrochemical Energy Reviews》 SCIE EI CSCD 2023年第1期320-356,共37页
Solid-state lithium-metal batteries(SLMBs)have been regarded as one of the most promising next-generation devices because of their potential high safety,high energy density,and simple packing procedure.However,the pra... Solid-state lithium-metal batteries(SLMBs)have been regarded as one of the most promising next-generation devices because of their potential high safety,high energy density,and simple packing procedure.However,the practical applications of SLMBs are restricted by a series of static and dynamic interfacial issues,including poor interfacial contact,(electro-)chemical incompatibility,dynamic Li dendrite penetration,etc.In recent years,considerable attempts have been made to obtain mechanistic insight into interfacial failures and to develop possible strategies towards excellent interfacial properties for SLMBs.The static and dynamic failure mechanisms at interfaces between solid electrolytes(SEs)and electrodes are comprehensively summarized,and design strategies involving interfacial modification,electrode/SE engineering,and the monolithic construction of SLMBs are discussed in detail.Finally,possible research methodologies such as theoretical calcu-lations,advanced characterization techniques,and versatile design strategies are provided to tackle these interfacial problems. 展开更多
关键词 Solid-state batteries Interfacial issues Interfacial modification Electrode/solid-electrolyte engineering Monolithic construction
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Early Serum HBsAg Kinetics as Predictor of HBsAg Loss in Patients with HBeAg-Negative Chronic Hepatitis B after Treatment with Pegylated Interferonα-2a 被引量:17
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作者 Minghui Li Lu Zhang +7 位作者 Yao Lu qiqi chen Huihui Lu Fangfang Sun Zhan Zeng Gang Wan Linqing Zhao Yao Xie 《Virologica Sinica》 SCIE CAS CSCD 2021年第2期311-320,共10页
Hepatitis B surface antigen(HBsAg)loss is an ideal treatment endpoint for patients with chronic hepatitis B(CHB).We investigated the predictive value of on-treatment HBsAg levels for HBsAg loss in hepatitis B e antige... Hepatitis B surface antigen(HBsAg)loss is an ideal treatment endpoint for patients with chronic hepatitis B(CHB).We investigated the predictive value of on-treatment HBsAg levels for HBsAg loss in hepatitis B e antigen(HBe Ag)-negative CHB patients who received 120-week PEG-IFNα-2a treatment.Serum HBV DNA,HBsAg,and anti-HBs levels were assayed at baseline and every 3 months during the treatment.Of 81 patients,12 achieved HBsAg loss,20 achieved HBsAg\100 IU/mL,and 49 maintained HBs Ag C 100 IU/mL.HBsAg loss rate was only 3.7%at 48 weeks,while it reached to 11.1%and 14.8%after treatment of 96 weeks and 120 weeks.The cutoff HBs Ag levels at 12 weeks predicting HBsAg loss at 96 weeks and 120 weeks of treatment were 400 IU/mL and 750 IU/mL,with AUC 0.725 and 0.722,positive predictive value(PPV)29.41%and 30.56%,and negative predictive value(NPV)93.75%and 97.78%,respectively.The cutoff HBsAg levels at 24 weeks predicting HBsAg loss at 96 weeks and 120 weeks of treatment were 174 IU/m L and 236 IU/mL respectively,with AUC 0.925 and 0.922,PPV 40.0%and 46.15%,and both NPV 100%.The predictive ability of the cutoff HBsAg levels at 24 weeks was better than that at 12 weeks for HBs Ag loss at either 96 or 120 weeks(χ~2=3.880,P=0.049 andχ~2=4.412,P=0.036).These results indicate that extended therapy is critical to HBsAg loss in HBe Ag-negative CHB patients during PEG-IFN treatment,and the HBsAg level at 24 weeks can be used to predict HBsAg loss during tailoring PEG-IFN therapy. 展开更多
关键词 Chronic hepatitis B(CHB) Hepatitis B surface antigen(HBsAg) Pegylated interferon HBsAg loss HBeAg negative
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