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181.

The cathelicidin-derived peptide (CDP1) is a human antimicrobial peptide that preferentially targets bacterial membranes in response to infection. CDP1 was functionalised with NODAGA and DOTA for complexation with gallium-68 to evaluate its potential as an infection imaging tracer. The synthesis of [68Ga]Ga–NODAGA–CDP1 and [68Ga]Ga–DOTA–CDP1 were optimised for pH, molarity, incubation time and temperature, and product purification. The integrity and protein binding were investigated employing [68Ga]GaCl3 and [68Ga]Ga–DOTA–TATE as internal references. [68Ga]Ga–NODAGA–CDP1 displayed good labelling properties with higher product yield compared to [68Ga]Ga–DOTA–CDP1. In contrast, [68Ga]Ga–DOTA–CDP1 showed better stability and is the preferred candidate for an in vivo investigation.

  相似文献   
182.
We used the one-step hydrothennal controlled synthesis method for Co-Ni3S2 ultrathin nanosheets grown directly on nickel foam(NF).The as-synthesized Co-Ni3S2/NF showed eiilianced activities in the hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and better overall water splitting(OWS)efficiency than the iin-doped Ni3S2/NF.the voltage of Co-Ni3S2/NF for OWS was only 1.58 V at the current density of 10 niA/cm^2 and with long time(>30 h)current output during the current-density(i-t)test.The good i-t pertonnance was also observed in both HER and OER processes.Additionally,the Co-Ni3S2/NF showed a large current density(>1A/cm^2)for both HER and OER.Wlien the current densities reached 100 and 1000 mA/cm^2,the required overpotentials tor Co-Ni3S2/NF were 0.35 and 0.75 V for OER and 0.30 and 0.85 V for HER.Therefore,after introducing Co,the activity of Ni3S2-based material was strongly enhanced.  相似文献   
183.
针对热集成系统换热网络存在的严重非凸非线性与多维多极值问题,提出动态多智能体微分进化算法.结合动态更新策略,并引入多智能体算法的环境感知能力,改进微分进化算法的种群生成方式与变异机制,并增强在大规模复杂非线性系统中的全局搜索能力.通过10SP2与9SP1换热网络经典算例优化,得到最佳年综合费用,体现出了改进算法更优的全局搜索能力.  相似文献   
184.
Exploitation of stimuli-responsive nanoplatforms is of great value for precise and efficient cancer theranostics. Herein, an in situ activable “nanocluster-bomb” detonated by endogenous overexpressing legumain is fabricated for contrast-enhanced tumor imaging and controlled gene/drug release. By utilizing the functional peptides as bioligands, TAMRA-encircled gold nanoclusters (AuNCs) endowed with targeting, positively charged and legumain-specific domains are prepared as quenched building blocks due to the AuNCs'' nanosurface energy transfer (NSET) effect on TAMRA. Importantly, the AuNCs can shelter therapeutic cargos of DNAzyme and Dox (Dzs-Dox) to aggregate larger nanoparticles as a “nanocluster-bomb” (AuNCs/Dzs-Dox), which could be selectively internalized into cancer cells by integrin-mediated endocytosis and in turn locally hydrolyzed in the lysosome with the aid of legumain. A “bomb-like” behavior including “spark-like” appearance (fluorescence on) derived from the diminished NSET effect of AuNCs and cargo release (disaggregation) of Dzs-Dox is subsequently monitored. The results showed that the AuNC-based disaggregation manner of the “nanobomb” triggered by legumain significantly improved the imaging contrast due to the activable mechanism and the enhanced cellular uptake of AuNCs. Meanwhile, the in vitro cytotoxicity tests revealed that the detonation strategy based on AuNCs/Dzs-Dox readily achieved efficient gene/chemo combination therapy. Moreover, the super efficacy of combinational therapy was further demonstrated by treating a xenografted MDA-MB-231 tumor model in vivo. We envision that our multipronged design of theranostic “nanocluster-bomb” with endogenous stimuli-responsiveness provides a novel strategy and great promise in the application of high contrast imaging and on-demand drug delivery for precise cancer theranostics.

An in situ activable “nanocluster-bomb” detonated by endogenous overexpressing legumain is fabricated for contrast enhanced cancer imaging and effective gene/chemo-therapy.  相似文献   
185.
以吲哚为骨架,在吲哚的1位、3位引入2条边臂基团得到了1,3‐双取代吲哚基化合物,用丁基锂去质子后与MCl4(M=Ti、Zr、Hf)反应,得到一系列NCN钳型钛、锆、铪金属配合物(3-Ti3-Zr3-Hf)。该系列配合物以核磁、元素分析及单晶X射线衍射进行了表征。单晶结构显示,金属中心除与3个氯原子配位外,还与配体以κ3NCN的形式配位,形成六配位的八面体构型。考察了该类型配合物在不同助催化体系条件下催化苯乙烯聚合反应的性能。实验发现:在室温下,助催化剂为 AlEt2Cl/(Ph3C)[B(C6F5)4],甲苯为溶剂,单体与催化剂在浓度比300∶1的条件下,不同金属中心配合物都能以高转化率得到聚苯乙烯,其中铪配合物的催化活性最高。催化所得的聚苯乙烯经表征发现均为无规结构,数均分子量为4 000~8 000。  相似文献   
186.
Organic materials with redox-active centers are regarded as promising candidates for rechargeable batteries in recent years for their light weight, low cost, en...  相似文献   
187.
水系锌离子电池具有成本低廉、环境友好、安全、能量密度较高等特点,有望应用于大规模电化学储能装置.然而,目前使用的商业化锌箔负极相对正极活性材料大大过量,显著降低了电池的能量密度,且存在严重的穿孔和极耳脱落等问题.使用集流体负载锌作为负极可有效提高放电深度,同时避免电极穿孔失效.但是,集流体界面易产生锌枝晶与副反应,严重影响电池的循环寿命.本综述首先分析了锌枝晶与副反应的产生原因及其对锌负极电化学性能的影响,并从集流体材料成分选择与结构构建两方面总结了锌负极集流体的设计思路,包括选择亲锌性材料、设计择优取向基底与构建三维集流体结构.设计合适的集流体可有效调控锌金属的沉积与剥离行为,从而推进水系锌离子电池的实用化.  相似文献   
188.
For an upper triangular matrix ring, an explicit ladder of height 2 of triangle functors between homotopy categories is constructed. Under certain conditions, the author obtains a localization sequence of homotopy categories of acyclic complexes of injective modules.  相似文献   
189.
采用传统高温固相法合成了系列Fe掺杂钐镓石榴石Sm3Ga5-xFexO12(x=1,2,3,4)可逆热致变色材料, 并通过粉末X射线衍射(XRD)、 红外光谱(FTIR)、 拉曼光谱(Raman)、 扫描电子显微镜(SEM)、 X射线光电子能谱(XPS)及固体紫外光谱分析技术研究了物质的结构及性质. 在室温下, 随着铁掺杂量的增加, 样品的颜色从亮黄绿色逐渐变为深墨绿色, 且随着温度从室温升至500 ℃, 样品的颜色也逐渐变为相应的橘黄色和棕色. 样品在室温下所呈现的黄绿色是源于其在紫色光区域及橙红色光区域内有相应的吸收行为, 且随着温度的升高, 吸收行为持续红移, 样品颜色也随之发生变化.  相似文献   
190.
杜宇轩  江涛  常美佳  戎豪杰  高欢欢  尚玉 《化学进展》2022,34(12):2715-2728
近年来基于稠环电子受体的有机太阳能电池发展迅速,然而稠环受体分子结构的复杂性导致了较高的合成成本和较低的收率,限制了其商业化应用。非稠环小分子受体因其采用C-C单键连接,因具有分子结构简单、结构多样性、合成成本低等优点获得广泛关注。本文从材料设计角度入手,围绕非稠环电子受体的发展历程,简要讨论结构调控对材料基本性质、聚集态结构、分子堆积、活性层形貌及相应光伏性质的影响规律;重点介绍关于完全非稠环受体材料的结构-性质之间的关系。最后从材料设计、器件优化、器件光伏性能、器件稳定性方面对非稠环受体材料的发展做出展望。  相似文献   
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