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111.
Zhaojuan Zheng Qianqian Xu Peng Liu Fan Zhou Jia Ouyang 《Applied biochemistry and biotechnology》2018,186(1):122-131
In order to find an alternative for commercial inulinase, a strain XL01 identified as Penicillium sp. was screened for inulinase production. The broth after cultivated was centrifuged, filtered, and used as crude enzyme for the following saccharification. At pH 5.0 and 50 °C, the crude enzyme released 84.9 g/L fructose and 20.7 g/L glucose from 120 g/L inulin in 72 h. In addition, simultaneous saccharification and fermentation of chicory flour for d-lactic acid production was carried out using the self-produced crude inulinase and Lactobacillus bulgaricus CGMCC 1.6970. A high d-lactic acid titer and productivity of 122.0 g/L and 1.69 g/(L h) was achieved from 120 g/L chicory flour in 72 h. The simplicity for inulinase production and the high efficiency for d-lactic acid fermentation provide a perspective and profitable industrial biotechnology for utilization of the inulin-rich biomass. 相似文献
112.
共价有机框架材料在多相催化领域的研究进展(英文) 总被引:1,自引:0,他引:1
共价有机框架(COFs)材料是近年来在拓扑学基础上发展起来的一类新型有机多孔聚合物,是有机单体通过可逆共价键连接而形成的晶型多孔材料,具有拓扑结构"可设计"、比表面积大、结构规整、孔道均一、孔径可调节以及易于修饰和功能化等优点.与金属有机框架材料(MOFs)相比,由于COFs是以共价键连接形成空间网络结构,具有较好的热稳定性和化学稳定性,又被称为"有机分子筛".COFs的构筑单体为有机小分子,有机小分子来源广泛而且种类繁多,使得构筑单体多样化,便于通过构筑单体来调控目标材料的结构和功能.自2005年首次报道以来,COFs以其独特的结构和优越的性能,吸引了广大科研工作者的极大兴趣,对其结构设计、可控合成、结构解析以及功能探索成为了研究热点,在气体吸附与分离、光电材料等领域展现出了广阔的应用前景.特别是在催化领域,由于COFs材料的多孔性、敞开的孔道结构、良好的稳定性以及易于修饰的特点,采用COFs作为催化剂以及催化剂载体受到了人们普遍的关注.作为催化剂,COFs可分为本征型催化剂和负载型催化剂.本征型催化剂的设计方法是基于"自下而上"策略将催化活性中心嵌入材料骨架之中;负载型催化剂的设计方法是以COFs为载体,通过后修饰方式负载金属颗粒或离子来构建多相催化剂.本征型COFs催化剂是在分子水平上引入催化活性中心,具有活性位点均匀分散、数量可控的特点,而且COFs规整均一的孔道结构有利于底物的传质,也为择形催化提供了可能;负载型催化剂通过后修饰方式引入催化活性中心,由于COFs以共价键连接,催化剂稳定性较高.COFs载体具有较大的比表面积,使得催化活性位点分散性好,也有利于底物与催化活性位点的结合.本文综述了COFs作为多相催化剂在催化领域的发展状况,按照COFs引入催化活性位点的类别,如单催化位点、双催化位点以及负载的金属纳米粒子进行了细致的阐述,重点讨论了COFs催化剂的设计理念、制备方式、功能化策略、材料的稳定性、催化活性以及选择性等内容.此外,对COFs作为光催化剂以及电催化剂方面的研究也进行了详细的介绍.最后,我们讨论了COFs在未来催化领域所面临的问题及挑战,并展望了COFs在超分子催化以及酶催化等方面的应用前景. 相似文献
113.
A new Pebax-based mixed matrix membrane with amide functionalized PCP filler shows promising CO2/N2 separation at ambient temperature. 相似文献
114.
Polymeric Nanoparticles with a Glutathione‐Sensitive Heterodimeric Multifunctional Prodrug for In Vivo Drug Monitoring and Synergistic Cancer Therapy 下载免费PDF全文
Dr. Fuwu Zhang Qianqian Ni Dr. Orit Jacobson Siyuan Cheng Arthur Liao Dr. Zhantong Wang Zhimei He Dr. Guocan Yu Dr. Jibin Song Dr. Ying Ma Dr. Gang Niu Dr. Longjiang Zhang Dr. Guizhi Zhu Dr. Xiaoyuan Chen 《Angewandte Chemie (International ed. in English)》2018,57(24):7066-7070
Polymeric micelle‐based drug delivery systems have dramatically improved the delivery of small molecular drugs, yet multiple challenges remain to be overcome. A polymeric nanomedicine has now been engineered that possesses an ultrahigh loading (59 %) of a glutathione (GSH)‐sensitive heterodimeric multifunctional prodrug (HDMP) to effectively co‐deliver two synergistic drugs to tumors. An HDMP comprising of chemotherapeutic camptothecin (CPT) and photosensitizer 2‐(1‐hexyloxyethyl)‐2‐devinyl pyropheophorbide‐α (HPPH) was conjugated via a GSH‐cleavable linkage. The intrinsic fluorogenicity and label‐free radio‐chelation (64Cu) of HPPH enabled direct drug monitoring by fluorescence imaging and positron emission tomography (PET). Through quantitative PET imaging, HDMP significantly improves drug delivery to tumors. The high synergistic therapeutic efficacy of HDMP‐loaded NPs highlights the rational design of HDMP, and presents exciting opportunities for polymer NP‐based drug delivery. 相似文献
115.
Yuanyuan Zhang Qianqian Liang Cheng Huang Ping Gao Hongbo Shu Xiaoyan Zhang Xiukang Yang Li Liu Xianyou Wang 《Journal of Solid State Electrochemistry》2018,22(7):1995-2002
Tavorite-structured lithium transition metal fluorophosphates have been considered as a good alternative to olivine-type cathode for lithium-ion batteries due to its exceptional ionic conductivity and excellent thermal stability. In this work, nearly monodisperse LiFePO4F nanospheres with high purity are successfully synthesized by a solid-state route associated with chemically induced precipitation method for the first time. The synthesized LiFePO4F presents nearly monodisperse nanospheres particles with average particle size of ~?500 nm. Cyclic voltammetry data exhibit a clear indication of the Fe3+/Fe2+ redox couple that involves a two-phase transition. Its electrochemical behaviors are examined by galvanostatic charge-discharge. The results show that the initial discharge capacity is 110.2 mAh g?1 at 0.5 C, after 200 cycles is still retained 104.0 mAh g?1 with the retention rate of 94.4%. The excellent cycle performance is mainly attributed to the uniform nanospheres-like morphology which is not only beneficial to shorten the transport distance of ions and electrons, but also improve the interface area between electrode and electrolyte, and thus improve the kinetics of Li ions. 相似文献
116.
117.
目的 比较青少年双相障碍Ⅱ型和单相抑郁症之间认知功能的差异。方法 对54 例青少年双相障碍Ⅱ型和83 例
青少年单相抑郁症患者在抑郁发作时作认知功能测验,包括:中国韦氏成人智力量表(WAIS-RC)、连线测验(TMT)、持续操作测验(CPT)、韦氏记忆量表(WMS-RC)、词语流畅性测验(VF)、威斯康星卡片分类测验- 改良版(WCST),并与50 例健康对照组比较。经过6 周治疗后,对抑郁症状缓解(HAMD≤7 分)患者重复上述认知功能测验。结果 入组时双相障碍Ⅱ型和单相抑郁两组在认知功能方面广泛受损,表现为TMT-A、WAIS-RC 数字符号、CPT、WAIS-RC 数字广- 倒背、WAIS-RC视觉再生、VF、WCST 和TMT-B项目上与健康人群相比明显成绩差,差异均有统计学意义(均P<0.01),但双相障碍Ⅱ型和单相抑郁两组间比较差异无统计学意义(P>0.05)。治疗6 周后,对两组临床痊愈的患者重复测验,发现两者在WAIS-RC 数字符号和WAIS-RC 视觉再生方面存在持续性损伤,与健康对照组比较差异均有统计学意义(P<0.05)。双相障碍Ⅱ型患者在CPT 项目上存在损伤,与健康对照组比较差异有统计学意义(P<0.05)。而单相抑郁症患者表现为VF和TMT-B 项目上存在损伤,与健康对照组比较差异有统计学意义(P<0.05)。结论 双相障碍Ⅱ型和单相抑郁在抑郁状态时,认知功能广泛受损,两者比较无统计学差异。在抑郁症状缓解后,双相障碍Ⅱ型表现为持续性注意
功能障碍,而单相抑郁表现为执行功能障碍。 相似文献
118.
119.
Zhao Yanteng Yang Qiankun Cheng Qianqian Ai Junjie Feng Mengna Wang Chengshuang Lv Xianping He Meng Chen Yun 《Cellulose (London, England)》2021,28(13):8527-8539
Cellulose - In the present study, we have in situ synthesized polypyrrole (PPy) on the hydroxyethyl cellulose/soy protein isolate (HEC/SPI) sponges to construct electro-conductive HEC/SPI/PPy... 相似文献
120.
Yanqi Wang Zhipeng Zhu Zhaofeng Sun Dr. Qianqian Hu Dr. Jianrong Li Prof. Jiang Jiang Prof. Xiaoying Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(7):1624-1632
Although supertetrahedral Tn sulfide clusters (n=2–6) have been extensively explored, the synthesis of Tn selenide clusters with n>4 has not been achieved thus far. Reported here are ionic-liquid (IL)-assisted precursor route syntheses, characterizations, and the photocatalytic properties of six new M-In-Q (M=Cu or Cd; Q=Se or Se/S) chalcogenide compounds, namely [Bmmim]12Cu5In30Q52Cl3(Im) (Q=Se ( T5-1 ), Se48.5S3.5 ( T5-2 ); Bmmim=1-butyl-2,3-dimethylimidazolium, Im=imidazole), [Bmmim]11Cd6In28Q52Cl3(MIm) (Q=Se ( T5-3 ), Se28.5S23.5 ( T5-4 ), Se16S36 ( T5-5 ); MIm=1-methylimidazole), and [Bmmim]9Cd6In28Se8S44Cl(MIm)3 ( T5-6 ). The cluster compounds T5-1 and T5-3 represent the largest molecular supertetrahedral Tn selenide clusters to date. Under visible-light illumination, the Cu-In-Q compounds showed photocatalytic activity towards the decomposition of crystal violet, whereas the Cd-In-Q compounds exhibited good photocatalytic H2 evolution activity. Interestingly, the experimental results show that the photocatalytic performances of the selenide/sulfide solid solutions were significantly better than those of their selenide analogues, for example, the degradation time of the organic dye with T5-2 was much shorter than that with T5-1 , whereas the photocatalytic H2 evolution efficiencies with T5-3 – T5-6 improved significantly with increasing sulfur content. This work highlights the significance of IL-assisted precursor route synthesis and the tuning of photocatalytic properties through the formation of solid solutions. 相似文献