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11.
Li  Zhenxing  Gong  Yixuan  Zhang  Xin  Wen  Yangyang  Yao  Jiasai  Hu  Mingliang  He  Miao  Liu  Jiahao  Li  Rui  Wang  Fuqiang  Zhang  Chuanxin 《Nano Research》2020,13(10):2812-2818

Carbon-carbon (C-C) coupling reactions represent one of the most powerful tools for the synthesis of complex natural products, bioactive molecules developed as drugs and agrochemicals. In this work, a multifunctional nanoreactor for C-C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8 (Cu@Ni@ZIF-8). In this nanoreactor, Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center, and Cu core was in situ heating source for the catalyst by absorbing the visible light. Moreover, benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8, the absorption range of nanoreactor was widened and the utilization rate of visible light was enhanced. Most importantly, the microporous structure of ZIF-8 provided shape-selective of reactant. This composite was used for the highly shape-selective and stable photocatalysed C-C coupling reaction of boric acid under visible light irradiation. After five cycles, the nanoreactor still remained high catalytical activity. This Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C-C coupling reactions with shape-selectivity.

  相似文献   
12.
ABSTRACT

Here, a novel cryogenic rolling plus intercritical annealing process was applied to a transformation-induced plasticity (TRIP) steel with a low chemical composition of carbon and manganese. Compared with traditional cold rolling, obvious grain refinement was observed, due to a high amount of dislocations retained. In addition, austenite volume fraction was increased, because of a unique nucleation mechanism. Subjected to cryogenic rolling, strength and ductility were increased, due to the enhanced austenite stability, which provided continuous and active TRIP effect. Consequently, tensile strength was increased to 1030?MPa, and elongation was increased to 38.2%. Thus, a great mechanical combination was obtained in a steel with a relatively low chemical composition with carbon and manganese, only by cryogenic rolling process.  相似文献   
13.
14.
In the network environment, the single time-triggered scheme wastes limited bandwidth resources due to all the sampled data are transmitted to the networks, and the single event-triggered scheme may increase system error because of ignoring factors such as changes in network utilization. To reduce the design conservatism, this paper is concerned with the hybrid-triggered L1 fault detection filter design for a class of nonlinear networked control systems (NCSs) described by Takagi–Sugeno (T-S) fuzzy model. Taking the effects of time-triggered scheme and event-triggered scheme into consideration simultaneously, we construct a fuzzy fault detection system. New results on stability and L1 performance are proposed for fuzzy fault detection system by exploiting the Lyapunov–Krasovskii functional and by means of the integral inequality method. Specially, attention is focused on the design of fault detection filter that guarantees a prescribed L1 noise attenuation level . Finally, two examples are presented to demonstrate the effectiveness of the proposed method.  相似文献   
15.
The gel-forming ability of myofibrillar protein (MP) is highly correlated with the characteristics of emulsified meat products. Incorporation of Agaricus bisporus (Ab) powder into MP gels may enhance its gel properties to facilitate the development of a novel and safe meat product. Therefore, this study investigated the effects of Ab powder on gel strength, water holding capacity (WHC), texture, rheological behaviour, LF-NMR spin–spin relaxation (T2), microstructure and protein secondary structure of the MP gel system. The results indicated that the gel strength, WHC, G' value and G" value were significantly improved when the addition of Ab powder increased from 0% to 6% (P < 0.05). Meanwhile, the T2 relaxation time was shortened, and free water was transformed into immobilised water. The texture of the gel was improved when 1%–4% Ab powder was added compared to the control. Furthermore, Ab filled in the gel network and promoted the unfolding of MP α-helix and the formation of MP β-sheet during the thermal denaturation of MP, leading to a dense aggregated network structure. The study suggested that Ab could be a promising ingredient in improving chicken MP's gel properties and developing fat-reduced meat products.  相似文献   
16.
李雨成  刘剑  鞠俊 《矿业快报》2007,23(4):26-28
从热力学的角度出发,考虑巷道热力因素对风流的影响,导出自然风压的计算方法。  相似文献   
17.
凹凸棒石黏土脱色剂对航空煤油脱色研究   总被引:1,自引:0,他引:1  
王青宁  申涛  李澜  朱琬荣 《非金属矿》2007,30(2):40-41,53
介绍了凹凸棒石黏土作为脱色剂,对航空煤油脱色.通过正交实验研究了活化酸度、焙烧温度、AlCl3加入量、脱色剂的用量和脱色时间对航空煤油脱色的影响.结果表明,经6%的硫酸酸化和450℃焙烧处理后的凹凸棒石黏土,加入1%AlCl;,制备的脱色剂脱色效果最佳,可使航空煤油的脱色率达到98.3%.  相似文献   
18.
膨胀石墨的尺寸效应及其对油吸附的影响   总被引:1,自引:1,他引:1  
用不同粒度的石墨在相同条件下酸化、高温膨胀,可获得膨胀倍数不同的膨胀石墨。通过扫描电镜及X射线衍射等观察膨胀石墨结构,证实在生产条件如酸氧化工艺、膨胀温度等相同时,鳞片石墨的粒度越大则膨胀倍数越高,对油的吸附性能越好。  相似文献   
19.
李奇 《工程建设》2007,39(2):56-59
介绍了我国医院工程建设的现状和特点,以及在此类工程建设中如何搞好监理工作。  相似文献   
20.
实施技术改造 ,加强生产管理 ,可有效解决粗煤泥对末煤跳汰系统的不利影响  相似文献   
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