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71.
72.
乡土建筑中蕴藏了大量符合生态的技术和理念,文章通过对豫东刘青霞故居乡土建筑的平面布局、空间形态、材料与结构、节能技术等方面进行分析和研究,发现其符合生态节能特征的因素主要有:故居檐廊和开敞的庭院创造了内外渗透、自然通风的生态环境;故居采用地方材料,具有造价低、污染小的生态节能性;故居的三段式立面,保证了结构受力的合理;故居厅堂和正房的屋面多做顶棚,墙体厚实,减少了热损耗,节能效果好.最后探讨了其对现代生态建筑设计的借鉴和启迪意义. 相似文献
73.
Two‐dimensional (2D) materials with atomic thicknesses have aroused great interest as promising building blocks for the preparation of ultrathin 2D membranes. These 2D membranes can exhibit unprecedentedly high separation permeance owing to their ultrasmall membrane thicknesses and superior selectivity because of their size‐selective nanopores and/or nanochannels. Until now, a large number of 2D membranes with good performance have been reported, highlighting the potential of these novel membranes for efficient liquid and gas separations. Summarized in this review are the latest advances in 2D membranes, with a special focus on industrially attractive separation processes, fabrication methods of laminar membranes, choices of membrane materials, designs of membrane structures, and unique membrane transport properties. Opportunities and challenges of 2D membranes for commercial applications are also briefly discussed. 相似文献
74.
The 12 principles of green chemistry are reviewed and applied specifically to polymer production. Examples of how the principles relate to current practice in polymer reaction engineering and which areas show the greatest potential impact for implementation of these principles are discussed. This paper does not attempt to be exhaustive but rather to target specific areas for further development. 相似文献
75.
Manganese(I)‐Catalyzed C−H Activation: The Key Role of a 7‐Membered Manganacycle in H‐Transfer and Reductive Elimination 下载免费PDF全文
Dr. Nasiru P. Yahaya Kate M. Appleby Magdalene Teh Conrad Wagner Erik Troschke Joshua T. W. Bray Prof. Simon B. Duckett L. Anders Hammarback Dr. Jonathan S. Ward Jessica Milani Dr. Natalie E. Pridmore Dr. Adrian C. Whitwood Dr. Jason M. Lynam Prof. Ian J. S. Fairlamb 《Angewandte Chemie (International ed. in English)》2016,55(40):12455-12459
Manganese‐catalyzed C?H bond activation chemistry is emerging as a powerful and complementary method for molecular functionalization. A highly reactive seven‐membered MnI intermediate is detected and characterized that is effective for H‐transfer or reductive elimination to deliver alkenylated or pyridinium products, respectively. The two pathways are determined at MnI by judicious choice of an electron‐deficient 2‐pyrone substrate containing a 2‐pyridyl directing group, which undergoes regioselective C?H bond activation, serving as a valuable system for probing the mechanistic features of Mn C?H bond activation chemistry. 相似文献
76.
生物质快速热解制车用燃料过程的能值分析 总被引:2,自引:0,他引:2
基于能值分析理论和考虑环境投入,从可持续发展的角度对玉米秸秆热解加氢制精制油过程的2个方案进行综合评价,获得生产效率、环境影响、可持续性方面的能值指标.方案1中的氢气来自初级生物油水相重整,方案2中氢气来自外部市场购买.结果表明:2个方案能值转换率分别为5.00×105sej/J和1.37×105sej/J,从能值转换率的角度分析,与方案1、玉米燃料乙醇及生物柴油相比,方案2生产等量燃料消耗的太阳能最少,更有优势;2个方案的能值产出率均为1.07,生产效率较低;环境负载率分别是1.02和1.05,对环境影响较小;可持续发展系数分别是1.05和1.02,可持续性属于中等水平. 相似文献
77.
本文从我国现行养老金政策出发,利用灰关联分析得到养老金收支的影响因素的排序,建立中国城乡居民养老金收支模型.然后利用Logistic人口预测模型估计出不同替代率下2013-2035未来23年我国养老金缺口,并利用仿真方法算出保证我国养老保险体系的可持续性的替代率的合理区间为50%-70%.进一步分析影响替代率各因素的灵敏性,并考虑延迟退休、做实个人账户以及市场化投资等因素对模型进行改进.最后以养老金替代率为切入点,对退休年龄等模型参数的调整和有关措施进行了分析与评价. 相似文献
78.
analyzing the challenges of China’s energy supply, an excellent perspective of nuclear power development in china has been described. Taking into account the midlong term development requirements, a comprehensive, coordinated and sustainable nuclear power strategic consideration and proposal is put forward. Thus our national nuclear industry can not only catch up with the world advanced level in proper time, but also possess the enough stamina of sustainability. 相似文献
79.
Hairul Hisham Hamzah Nur Hidayah Saleh Bhavik Anil Patel Mohd Muzamir Mahat Saiful Arifin Shafiee Turgut Snmez 《Molecules (Basel, Switzerland)》2021,26(1)
The development of low-cost electrode devices from conductive materials has recently attracted considerable attention as a sustainable means to replace the existing commercially available electrodes. In this study, two different electrode surfaces (surfaces 1 and 2, denoted as S1 and S2) were fabricated from chocolate wrapping aluminum foils. Energy dispersive X-Ray (EDX) and field emission scanning electron microscopy (FESEM) were used to investigate the elemental composition and surface morphology of the prepared electrodes. Meanwhile, cyclic voltammetry (CV), chronoamperometry, electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) were used to assess the electrical conductivities and the electrochemical activities of the prepared electrodes. It was found that the fabricated electrode strips, particularly the S1 electrode, showed good electrochemical responses and conductivity properties in phosphate buffer (PB) solutions. Interestingly, both of the electrodes can respond to the ruthenium hexamine (Ruhex) redox species. The fundamental results presented from this study indicate that this electrode material can be an inexpensive alternative for the electrode substrate. Overall, our findings indicate that electrodes made from chocolate wrapping materials have promise as electrochemical sensors and can be utilized in various applications. 相似文献
80.
Muhammad Zahid Maria Lodhi Zulfiqar Ahmad Rehan Hamna Tayyab Talha Javed Rubab Shabbir Ahmed Mukhtar Ayman EL Sabagh Robert Adamski Mohamed I. Sakran Dorota Siuta 《Molecules (Basel, Switzerland)》2021,26(11)
The formation of new scaffolds to enhance healing magnitude is necessarily required in biomedical applications. Granulation tissue formation is a crucial stage of wound healing in which granulation tissue grows on the surface of a wound by the formation of connective tissue and blood vessels. In the present study, porous hydrogels were synthesized using chitosan incorporating latex of the Calotropis procera plant by using a freeze–thaw cycle to stimulate the formation of granulation tissue and angiogenesis in wound healing applications. Structural analysis through Fourier transform infrared (FTIR) spectroscopy confirmed the interaction between chitosan and Calotropis procera. Latex extract containing hydrogel showed slightly higher absorption than the control during water absorption analysis. Thermogravimetric analysis showed high thermal stability of the 60:40 combination of chitosan (CS) and Calotropis procera as compared to all other treatments and controls. A fabricated scaffold application on a chick chorioallantoic membrane (CAM) showed that all hydrogels containing latex extract resulted in a significant formation of blood vessels and regeneration of cells. Overall, the formation of connective tissues and blood capillaries and healing magnitude decreased in ascending order of concentration of extract. 相似文献