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151.
The chemical composition engineering of lead halide perovskites via a partial or complete replacement of toxic Pb with tin has been widely reported as a feasible process due to the suitable ionic radius of Sn and its possibility of existing in the +2 state. Interestingly, a complete replacement narrows the bandgap while a partial replacement gives an anomalous phenomenon involving a further narrowing of bandgap relative to the pure Pb and Sn halide perovskite compounds. Unfortunately, the merits of this anomalous behavior have not been properly harnessed. Although promising progress has been made to advance the properties and performance of Sn‐based perovskite systems, their photovoltaic (PV) parameters are still significantly inferior to those of the Pb‐based analogs. This review summarizes the current progress and challenges in the preparation, morphological and photophysical properties of Sn‐based halide perovskites, and how these affect their PV performance. Although it can be argued that the Pb halide perovskite systems may remain the most sought after technology in the field of thin film perovskite PV, prospective research directions are suggested to advance the properties of Sn halide perovskite materials for improved device performance.  相似文献   
152.
A new 9,11‐secosteroid, (22R)‐22‐acetoxy‐3β,6α,11‐trihydroxy‐9,11‐seco‐5α‐cholest‐7‐en‐9‐one, along with twelve known analogues were isolated from the South China Sea gorgonian coral Iciligorgia sp. Their structures were determined by the spectroscopic analysis and comparison with reported data. In an in vitro test of osteoclastic differentiation, three compounds exhibited significant down‐regulating effect whereas two compounds showed significant up‐regulating effect at 0.5 and 1.0 μm . This is the first report of the chemical investigation of the gorgonian Iciligorgia sp. The acetoxy substitution at C‐22 seems to play an important role in the regulating activity.  相似文献   
153.
The introduction of 3D wettable current collectors is one of the practical strategies toward realizing high reversibility of lithium (Li) metal anodes, yet its effect is usually insufficient owing to single electron‐conductive skeleton. Here, homogeneous Li deposition behavior and enhanced Coulombic efficiency is reported for electrochemically lithiated Cu3P nanowires, owing to the formation of a mixed ion/electron‐conducting skeleton (MIECS). In particular, by evaluating the Gibbs free energy change, the possible chemical reaction between Cu3P and molten Li is used to construct a MIECS containing Li3P and Cu–Li alloy phase. The successful conversion of Cu3P nanowires to Li3P and Cu–Li alloy nanocomposite not only greatly reduces the surface energy between molten Li and Cu3P, but also induces uniform Li stripping/plating behavior via balanced ion/electron transport. Thus, the as‐obtained Li@MIECS composite anode displays superior cycling stability in both symmetric cells and full cells. This work provides a promising option for the preparation of high‐performance composite Li anodes containing MIECS by thermally pre‐storing Li.  相似文献   
154.
Bioprocess and Biosystems Engineering - Bioremediation methods have been successfully applied to the removal of organic pollutants for decades, but the responses of the microbial community to...  相似文献   
155.
目的:探讨中心静脉导管引流对单孔胸腔镜肺癌根治术患者术后胸腔引流的应用效果。方法:回顾性选取2019年1月至2019年12月期间我院收治的行单孔胸腔镜肺癌根治术患者80例的临床资料,根据引流方式的不同分为A组(n=40,传统引流)和B组(n=40,中心静脉导管引流),对比两组患者临床指标、生活质量、炎性因子及并发症发生情况。结果:B组引流操作时间、术后住院时间短于A组(P0.05)。两组术后3个月生活质量简表(SF-36)各维度评分均较术前升高,且B组高于A组(P0.05)。两组术前、术后3d、术后7d白介素-6(IL-6)、C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)呈先升高后下降趋势,且术后3d、术后7d B组以上指标低于A组(P0.05)。两组术后并发症发生率比较无差异(P0.05)。结论:与传统引流相比,单孔胸腔镜肺癌根治术患者术后采用中心静脉导管引流,效果显著,可减少炎性刺激,安全可靠,有效改善患者术后生活质量。  相似文献   
156.
目的:分析程序性死亡因子-1(PD-1)、程序性死亡1-配体(PD-L1)的表达与肺癌临床病理特征及预后的相关性。方法:回顾性分析我院2015年3月~2016年6月收治的73例肺癌患者的临床资料,取距离切除肿瘤边缘3cm内的非癌组织作为癌旁组织。比较两组PD-1、PD-L1的表达,分析其和肺癌患者临床病理特征和预后的关系,采用COX比例回归分析肺癌患者预后的影响因素。结果:肺癌组织PD-1、PD-L1阳性表达率均显著高于癌旁组织(P0.05)。不同性别、年龄、病理类型、吸烟情况、EGFR表达、肿瘤大小肺癌患者PD-1、PD-L1的阳性表达率比较差异无统计学意义(P0.05);低分化程度、临床分期Ⅲ及Ⅳ期、有淋巴结转移肺癌患者PD-1、PD-L1阳性表达率分别高于中分化程度、临床分期Ⅲ期、无淋巴结转移患者,差异有统计学意义(P0.05)。PD-1、PD-L1阳性表达及阴性表达组无疾病进展生存期比较均有统计学差异(P0.05)。COX比例风险回归模型显示分化程度、临床分期、淋巴结转移、PD-1、PD-L1的表达是影响肺癌患者预后的危险因素(P0.05)。结论:肺癌组织PD-1、PD-L1呈高表达,可能参与肺癌的发生发展,有助于病情严重程度的评价和预后预测。  相似文献   
157.
Chen  Junsen  Huang  Rui  Nie  Yiwen  Wen  Xinyue  Wu  Ying 《中国病毒学》2020,35(6):713-724
Virologica Sinica - Coronavirus disease 2019 (COVID-19), reminiscent of the severe acute respiratory syndrome (SARS) outbreak in 2003, has been a tragic disaster to people all over the world. As...  相似文献   
158.
Luo  Dan  Xia  Zhi  Li  Heng  Tu  Danna  Wang  Ting  Zhang  Wei  Peng  Lu  Yi  Wenfu  Zhang  Sai  Shu  Junhua  Xu  Hui  Li  Yong  Shi  Buyun  Huang  Chengjiao  Tang  Wen  Xiao  Shuna  Shu  Xiaolan  Liu  Yan  Zhang  Yuan  Guo  Shan  Yu  Zhi  Wang  Baoxiang  Gao  Yuan  Hu  Qinxue  Wang  Hanzhong  Song  Xiaohui  Mei  Hong  Zhou  Xiaoqin  Zheng  Zhenhua 《中国病毒学》2020,35(6):861-867
In December 2019, SARS-CoV-2 was first detected in the samples obtained from three adult patients who suffered from an unknown viral pneumonia in Wuhan (Li et al. 2020). This unknown viral pneumonia is further named as coronavirus disease 2019 (COVID-19) by the World Health Organization. To date, the number of new COVID-19 cases has continued to skyrocket and the impact of SARS-CoV-2 on humans is far greater than any pathogen of this century in both breadth and depth. Previous studies have shown that adults with COVID-19 have symptoms of fever, dry cough, dyspnea, fatigue and lymphocytopenia. Moreover, COVID-19 is more likely to cause death in the elderly, especially those with chronic comorbidities (Huang et al. 2020). In Wuhan, more than 50, 000 COVID-19 cases have been confirmed, including over 780 pediatric patients, and only one child death case (Lu et al. 2020). Although the number of children cases was far fewer than that of adults, COVID-19 might endanger children's health and the information on children remains limited, especially in serological study. In the retrospective study, the investigators analyzed the epidemiological, clinical and serological characteristics of children with COVID-19 in Wuhan in the early stages of the outbreak, which might provide theoretical and practical help in controlling COVID-19 and similar emerging infectious diseases in the future.  相似文献   
159.
柑橘木虱Diaphorina citri Kuwayama是柑橘黄龙病(huanglongbing,HLB)的重要传播媒介。为了利用灯光诱控技术防治柑橘木虱,本实验于室内条件下研究柑橘木虱对波长为360 nm、400 nm、440 nm、480 nm、520 nm、560 nm和600 nm的LED光源和不同光照强度趋光行为反应。结果表明:柑橘木虱对7种单色光都有正趋向性。其中雌雄混合存在时对400 nm的紫光趋向性最强,其次是560 nm的绿光;单独处理时,雌成虫对400 nm的紫光趋性最强,其次是520 nm的绿光,雄成虫则是对520 nm的绿光趋性最强,其次是400 nm的紫光。在200μw/cm 2到1000μw/cm 2的光照强度范围内,随着光照强度的增大,柑橘木虱雄成虫趋光行为逐渐增强,在光照强度为1000μw/cm 2时趋光行为最强,但雌成虫趋光行为变化不明显。该研究表明:柑橘木虱雌雄成虫具有明显的正趋光性,且对光谱和光强的反应存在差异。这一结果可为柑橘木虱田间的灯光诱控提供实验依据。  相似文献   
160.
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