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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Wei Wang Qi Han Zhijia Zhu Lishan Zhang Shan Zhong Baojiang Liu 《Advanced Powder Technology》2019,30(9):1882-1896
Photocatalytic performance of four tetracycline antibiotics using BiVO4/TiO2/RGO composites was investigated. To make full use of catalysis, optimum preparation conditions involved RGO content, solution pH and hydrothermal temperature on the structure forming of BiVO4/TiO2/RGO composites were investigated. Subsequently, the obtained visible light-driven photocatalyst was used to degrade four kinds of tetracycline antibiotics involved tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) for wastewater treatment. Results showed that BiVO4/TiO2/RGO photocatalyst exhibited excellent photocatalytic activity and high compatibility due to the enhanced separation efficiency of photo-generated carriers with high reduction and oxidation capability. The degradation process of four kinds of tetracycline antibiotics was traced and detected through identifying intermediates produced in the reaction system. And a possible catalytic mechanism for BiVO4/TiO2/RGO photocatalyst was put forward based on band gap structure of BiVO4 and TiO2. 相似文献
982.
Scientometrics - Collaboration among researchers plays an important role in scientific discoveries, especially in multidisciplinary research. How to allocate credit reasonably to coauthors of a... 相似文献
983.
984.
Chia‐Che Chang Sin‐Ren Li Hung‐Lung Chou Yi‐Cheng Lee Shivaraj Patil Ying‐Sheng Lin Chun‐Chih Chang Yuan Jay Chang Di‐Yan Wang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(49)
The generation of ammonia, hydrogen production, and nitrogen purification are considered as energy intensive processes accompanied with large amounts of CO2 emission. An electrochemical method assisted by photoenergy is widely utilized for the chemical energy conversion. In this work, earth‐abundant iron pyrite (FeS2) nanocrystals grown on carbon fiber paper (FeS2/CFP) are found to be an electrochemical and photoactive catalyst for nitrogen reduction reaction under ambient temperature and pressure. The electrochemical results reveal that FeS2/CFP achieves a high Faradaic efficiency (FE) of ≈14.14% and NH3 yield rate of ≈0.096 µg min?1 at ?0.6 V versus RHE electrode in 0.25 m LiClO4. During the electrochemical catalytic reaction, the crystal structure of FeS2/CFP remains in the cubic pyrite phase, as analyzed by in situ X‐ray diffraction measurements. With near‐infrared laser irradiation (808 nm), the NH3 yield rate of the FeS2/CFP catalyst can be slightly improved to 0.1 µg min?1 with high FE of 14.57%. Furthermore, density functional theory calculations demonstrate that the N2 molecule has strong chemical adsorption energy on the iron atom of FeS2. Overall, iron pyrite‐based materials have proven to be a potential electrocatalyst with photoactive behavior for ammonia production in practical applications. 相似文献
985.
986.
El‐Hajjaji Soundous Grard Amaury De Laubier Juliette Di Tanna Sybille Lain Aurlie Patz Viviane Sindic Marianne 《International Journal of Dairy Technology》2019,72(3):466-471
This study aims to describe the procedures and practices used in local production of raw milk butter. The demand for local products is increasing; hence, there is a need to describe the practices used in the artisanal production of raw milk butter. Therefore, a survey of 147 raw milk butter producers was carried out. The results from the survey indicate that there is not one single way to produce butter at artisanal level. In terms of maturation, six temperature sequences were distinguished. Attention is required at every step of production starting from breeding. 相似文献
987.
988.
目的 建立包衣糖果中柠檬黄、日落黄、胭脂红、诱惑红和亮蓝5种铝色淀的超高效液相色谱测定方法.方法 用NaOH溶液浸泡提取包衣糖果中的色淀,以乙腈-乙酸铵(10 mmol/L)为流动相,梯度洗脱,多波长检测定量.结果 5种目标化合物在0.25~50 mg/L范围内呈良好的线性,相关系数R2 >0.999.该方法中5种目标化合物的定量限(LOQ)均为1.0 mg/kg.在1、5、25 mg/kg三个添加浓度水平下,5种目标化合物的加标回收率为79.5% ~116.4%,RSD为0.92% ~6.48%.结论 该方法简单、快速、准确,适于包衣糖果中5种铝色淀的同时检测. 相似文献
989.
990.
为阐明麝香草酚的抑菌作用,采用滤纸片法、牛津杯法和扩散法(打孔法)等体外抑菌实验对食品中常见的10种污染菌进行抑菌作用研究,并测定麝香草酚对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、变形杆菌、保加利亚乳杆菌、嗜热乳酸链球菌、异常汉逊氏酵母、酿酒酵母、黑曲霉、黄曲霉的最低抑菌质量浓度。结果表明:麝香草酚抑菌谱广,对食品中常见污染菌有一定抑制作用,其中对细菌的抑菌效果最好。麝香草酚对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌的最低抑菌质量浓度分别为10、20、20μg/mL。 相似文献