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1.
Lin ZHUANG 《物理化学学报》2017,33(7):1269-1270
<正>二氧化碳电催化还原,以可再生电能或富余核电等洁净电能为能源,可以在温和的反应条件下将二氧化碳一步转化为一氧化碳、甲酸、碳氢化合物和醇类等高附加值化工原料及化学品,将二氧化碳"变废为宝"的同时实现了洁净电能的有效存储~1。当前,设计高效电催化剂来降低过电势和提高反应选择性是二氧化碳电催化还原研究中极具挑战性的热点课题。  相似文献   

2.
吴长顺 《化学教育》2015,36(13):73-73
基于初中化学有关"二氧化碳性质"教学的素材, 各种版本化学教科书、教参以及期刊中对实验的改进, 遵照教学大纲或课标要求, 优化了二氧化碳物理性质(密度比空气大、能溶于水)和化学性质(不能供给呼吸、能与水反应等)的实验方案, 例如:实验设计的呈现方式、对比性、简约性、成功率、化解学生疑惑的效果等。  相似文献   

3.
分析了教科书上"二氧化碳灭火"实验和"二氧化碳与水反应"实验的不足之处,并将这2个实验结合在一起进行了设计.新设计的实验成功率高、效果明显、趣味性强.  相似文献   

4.
设计3套"氢氧化钠溶液与二氧化碳气体反应"的实验装置,依据实验现象和二氧化碳气体的溶解度,很容易得出2者发生化学反应的实验结论。  相似文献   

5.
近年来, 二氧化碳过量排放所引发的全球变暖等气候问题引起了全世界的广泛关注, 碳减排已成为人类社会可持续发展面临的共同挑战. 利用电化学方法将二氧化碳转化为高附加值化学品是实现碳减排和二氧化碳高附加值利用的理想途径之一, 但仍面临能耗高、 二氧化碳转化率低、 产物选择性差和难分离等问题. 本文以电还原二氧化碳制草酸为例, 从反应机理、 催化剂、 电解液、 催化电极及反应器等方面介绍该反应的研究进展, 对当前二氧化碳电还原制草酸存在的关键问题进行了分析, 并对其未来研究方向进行了展望.  相似文献   

6.
董家骧 《化学教育》1986,7(4):45-45
我们利用二氧化碳灭火器来直接制取"干冰"("干冰雪")。制作手续比较简单,在一般学校里,都可以办到。同时还可以利用"干冰"做几个二氧化碳性质的实验,效果很好。  相似文献   

7.
苏沛锋  倪金煜  柯卓锋 《有机化学》2023,(10):3526-3543
利用二氧化碳作为C1原料进行硅氢化转化,是可持续性催化合成的重要方法之一.该方法能够将二氧化碳转化为不同氧化水平的高值化学品,例如甲酸、甲醛、甲醇和甲烷等.此外,胺可在特定的催化体系中与二氧化碳和硅烷多组分反应,实现基于二氧化碳硅氢化的N—H键酰基化和烷基化等转化.近年来,二氧化碳硅氢化领域的相关研究取得了显著的进展.综述了近三年来应用于二氧化碳硅氢化的主要均相催化体系的研究进展,介绍和总结催化剂的设计和相关催化性能,包括贵金属催化、廉价过渡金属催化、稀土金属催化、主族金属催化和无金属催化等催化体系,并讨论和展望了目前二氧化碳硅氢化的研究现状和潜在挑战.  相似文献   

8.
二氧化碳引起的全球温室效应不断在扩大,全球对健康、环保也更加重视,各个国家的相关投资也不断增大。上市公司台湾热映光电顺应市场需求推出ZG106系列二氧化碳监测仪,该仪器是一种掌上型高精度二氧化碳监测仪,当二氧化碳浓度达到1000μmol/mol时发出警报,并记录过去24h测量值以及最大和最小值,带给人们更舒适、健康、安全的环境。该二氧化碳监测仪可用于政府机关、办公室、写字楼、学校幼儿园、商场、医院、酒吧、歌舞厅、图书馆等公共场所和家庭中的环境监测,可以方便地知道是否需要通风换气,确保环境空气质量和节能的需要。另外,二氧化碳监测仪还是农业种植、畜牧业养殖等工业农业生产等多个领域必的监测设备。燃太ZG106系列二氧化碳监测仪全球上市@林  相似文献   

9.
正据悉,为有效掌握全球二氧化碳分布情况,"十二五"国家863计划设置了"全球二氧化碳监测科学实验卫星与应用示范"重大项目(简称"碳卫星")。目前中国首颗"碳卫星"载荷研制已进入冲刺阶段,卫星将于2016年5月正式出场,并于2016年8月发射。  相似文献   

10.
简要介绍了二氧化碳基塑料的工业化进程,同时针对当前二氧化碳共聚物结构中缺少可反应基团、难以进行化学修饰导致的品种和功能单一、亲水性差等问题,介绍了二氧化碳基脂肪族聚碳酸酯的功能化研究进展,主要包括侧链含有双键、碳酸酯键和液晶基团的侧基功能化二氧化碳共聚物的合成与性能研究,以及二氧化碳共聚物的亲水性调制和刺激响应行为探索,试图为丰富二氧化碳基聚碳酸酯结构和性能提供借鉴.  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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