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991.
A novel method for the selective oxidation of various types of sulfides to sulfoxides using chlorine dioxide as the oxidant is proposed. 相似文献
992.
Kharitonov A. B. Fomkin A. A. Pribylov A. A. Sinitsyn V. A. 《Russian Chemical Bulletin》2001,50(4):591-594
Carbon dioxide adsorption on the microporous carbon adsorbent PAU-10 within the 177.8—423 K temperature and 0.1—5.13·106 Pa pressure intervals was studied. The isosteres of absolute adsorption are well approximated by straight lines, which do not change their slope on going to temperatures higher than the critical temperature of CO2. An increase in the differential molar isosteric heat of adsorption (q
st) at 0 < a < 1 mmol g–1 is explained by the influence of the endothermic effect of adsorption expansion of the adsorbent. In the region of high pressures and nonideal gas phase, q
st is temperature-dependent. 相似文献
993.
基于环糊精/卟啉包络物荧光猝灭的二氧化碳光学敏感膜的研究 总被引:6,自引:0,他引:6
全 -( 2 ,6-二 -O-异丁基 ) -β-环糊精 ( DOB-β-CD)对固定于增塑 PVC膜中的 meso-四 ( 4-甲氧基苯基 )卟啉( TMOPP)有明显的荧光增强效应 ,且该荧光可被溶液中的二氧化碳可逆猝灭 .本文据此研制了一种可用于测定水溶液中二氧化碳含量 ,即 [H2 CO3]浓度的荧光敏感膜 .研究了最佳膜的组成 .经过组成优化的敏感膜测定 [H2 CO3]浓度的范围为 4 .75× 1 0 - 7~ 3.9× 1 0 - 5 mol/L.该传感器响应迅速、重现性好 ,常见的离子无明显干扰 . 相似文献
994.
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997.
Noor Atiqah Aizan Abdul Kadir Azrina Azlan Faridah Abas Intan Safinar Ismail 《Molecules (Basel, Switzerland)》2021,26(18)
There has been growing interest among food scientists in producing a toxin-free fat as an end product with varying physical or nutritional properties of interest to the food industry. Oleoresin is a rich source of bioactive compounds which consumers can easily add to a large variety of food. Dabai (Canarium odontophyllum) pulp oleoresin (DPL) was extracted using supercritical carbon dioxide (SC-CO2) extraction, a green extraction technology. This study investigates the quality of SC-CO2 extracted DPL in discovering its potential as a new alternative fat. The extraction experiment was carried out at a pressure of 40 MPa and a temperature of 40 °C. DPL is a saturated fatty acid (SFA)-rich fat due to its high SFA composition (47.72 ± 0.01%). In addition, the low content of peroxide value (PV) (5.60 ± 0.09 mEq/kg) and free fatty acids (FFA) (3.40 ± 0.03%) indicate the quality and stability of DPL for various applications besides food consumption. DPL also has a low slip melting point (SMP) (20.20 ± 0.03 °C), and HPLC-FID revealed that DPL contained 0.13 ± 0.02 mg/100 g of vitamin E (α-tocopherol), indicating its potential application as a solid fat with a bioactive compound. This present work demonstrates the possible prospect of DPL in the formulation of end products for food industries. 相似文献
998.
Kirill V. Kholin Mikhail N. Khrizanforov Vasily M. Babaev Guliya R. Nizameeva Salima T. Minzanova Marsil K. Kadirov Yulia H. Budnikova 《Molecules (Basel, Switzerland)》2021,26(18)
A selective noble-metal-free molecular catalyst has emerged as a fruitful approach in the quest for designing efficient and stable catalytic materials for CO2 reduction. In this work, we report that a sodium pectate complex of copper (PG-NaCu) proved to be highly active in the electrocatalytic conversion of CO2 to CH4 in water. Stability and selectivity of conversion of CO2 to CH4 as a product at a glassy carbon electrode were discovered. The copper complex PG-NaCu was synthesized and characterized by physicochemical methods. The electrochemical CO2 reduction reaction (CO2RR) proceeds at −1.5 V vs. Ag/AgCl at ~10 mA/cm2 current densities in the presence of the catalyst. The current density decreases by less than 20% within 12 h of electrolysis (the main decrease occurs in the first 3 h of electrolysis in the presence of CO2). This copper pectate complex (PG-NaCu) combines the advantages of heterogeneous and homogeneous catalysts, the stability of heterogeneous solid materials and the performance (high activity and selectivity) of molecular catalysts. 相似文献
999.
1000.
IntroductionThe carbon dioxide concentration in atmosphere increases rapidly because of the development of industry, the notabe increasing use of petroleum fuel/coal and the gradual reductionof green plants. From 1920s to 1980s, the concentration of carbon dioxide in atmosphere was650 mg/m', in some big cities, it reached 786 mg/m'. At present, the concentration of carbon dioxide is between 638--1965 mg/m'['j.Much attention has not been paid to the effect of the increasing carbon dioxide conce… 相似文献