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991.
研究了海带浆体对马铃薯淀粉的糊化特性和油炸膨化特性的影响。研究表明,海带浆体对淀粉糊化的影响有利于膨化工艺操作,桨体含量50%,糊化淀粉比例8~10%,控制切片干燥后水份含量9%,可得到一种含碘≥50μg/100g,且综合感官评定效果最好的海带马铃薯油炸膨化食品。 相似文献
992.
磷酸根与磷酸基水化作用之比较—红外光谱研究 总被引:1,自引:0,他引:1
本文运用傅立叶变换红外光谱,对水/NaDEHP/正庚烷反胶束体系中的磷酸根及磷酸三丁酯-水体系中磷酸基的水化作用进行了研究。 相似文献
993.
Wengui Weng Guohua Chen Dajun Wu Xiangfeng Chen Jinrong Lu Pingping Wang 《Journal of Polymer Science.Polymer Physics》2004,42(15):2844-2856
In this study, the nylon 6/foliated graphite (FG) electrically conducting nanocomposites with a low percolation threshold of less than 0.75 vol % have been prepared via an in situ polymerization approach in the presence of FG nanosheet filler. Based on laser counting, scanning electron microscopy, transmission electron microscopy, and X‐ray diffraction characterization techniques, the structures and morphologies of the nanoscale filling particles and the resulting nanocomposites were examined. Using percolation theory, the conductivity behavior of the nanocomposite samples were modeled and analyzed. Through the use of mean‐field and excluded volume approaches, it was demonstrated that the experimentally observed percolation threshold values could be approximately estimated, and a correlation between the percolation threshold and the aspect ratio of FG particles could be quasi‐quantitatively established. Also, preliminary studies on the effects of FG nanosheets on the thermal properties of the host nylon 6 were performed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2844–2856, 2004 相似文献
994.
Yuan Weng Yuping Xu Chunjing Yu Weixing Wan Donghui Pan Lizhen Wang Min Yang 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1525-1529
The usability of 99mTc-spermine for human breast tumor imaging was evaluated. Mice bearing MDA-MB-231 breast tumor were used for SPECT imaging and biodistribution study. Tumor was imaged clearly after injection with 99mTc-spermine. The accumulation of 99mTc-spermine was much lower in chest region than that of general breast tumor imaging agent 99mTc-MIBI. It suggests that 99mTc-spermine is promising for breast cancer imaging. 相似文献
995.
为了发现新型姜黄素类抗肿瘤先导化合物,通过1,3-偶极环加成反应合成了14个螺杂环单羰基姜黄素类似物.该反应利用无需加催化剂的"一锅煮"方法合成,具有环境友好的优点.所有化合物结构经ESI-MS、ESI-HRMS和1H NMR确认,通过X衍射确证B6的晶体结构为单斜晶系,该类化合物的合成具有良好的区域选择性和立体选择性.通过噻唑兰(MTT)法测定所有化合物对人胃癌细胞SGC-7901、神经胶质瘤细胞U251、人大细胞肺癌细胞株NCI-H460的增殖抑制活性,部分化合物表现出了较好的活性.其中B1、B6、B7和B11对三种肿瘤细胞均表现出较好的抗肿瘤活性,而对正常人肝细胞HL-7702显示了相对较低的细胞毒性.化合物B1和B7均能明显诱导凋亡相关蛋白含半胱氨酸的天冬氨酸蛋白水解酶3(caspase3)和多聚ADP-核糖聚合酶(PARP)的活化,诱导肿瘤细胞发生凋亡.所合成的螺杂环单羰基姜黄素类似物为新型的抗肿瘤化合物,该类化合物可能在靶向抗肿瘤药物研发方面具有较好的研究前景. 相似文献
996.
采用原位显微Raman光谱和18O同位素示踪技术,以325 nm激光为激发光源,对立方Nd2O3上过氧物种的光诱导生成过程进行了详细表征,进一步证实过氧源于分子氧对晶格氧的氧化反应. 结果还表明,325 nm激光在室温下即可诱导过氧的生成,在实验条件下,生成的过氧物种可与Nd2O3的晶格氧发生快速的氧交换反应,位于Nd2O3体相的晶格氧也可迁移至样品表层进而参与过氧的生成. 325 nm激光照射有助于促进晶格氧的迁移以及晶格氧与分子氧之间的氧交换反应. 相似文献
997.
Mei-Li You Sheng-Yi Weng Min-Siou Liao Can-Yong Jhu Yun-Ting Tsai Quentin Lineberry Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2014,116(3):1453-1459
Isoprene monomer (IPM) is a colorless, volatile liquid obtained from petroleum or coal tar that occurs naturally in many process plants. It is used chiefly to make synthetic rubber. Our study used calorimetric approaches to conduct thermal analysis and hazard assessment of aluminum oxide (Al2O3) and IPM relevant studies. Differential scanning calorimetry, thermal activity monitor III, thermogravimetry, and vent sizing package 2 were used to discuss thermal instability reaction of Al2O3, which adsorbed IPM, and find every possible reason for cases of fire to prevent any future recurrence of the package store and transport related hazards. By means of calorimetric analysis technology, we can observe thermal decomposition or mass loss for different adsorbed concentrations of IPM and Al2O3 to discuss the related thermal stability parameters, such as exothermic onset temperature (T 0), heat of decomposition (ΔH d), self-accelerating exothermic rate (dT dt ?1), pressure rise rate, and maximum reaction temperature (T max). Then, we can understand the potential hazard factors that contribute to disasters related to processing, transport, and storage of security controls and reaction process design. 相似文献
998.
Yan Shao Dan‐Wei Ou‐Yang Wen Gao Liang Cheng Xiao‐Xiang Weng De‐Yun Kong 《Helvetica chimica acta》2014,97(7):992-998
Three new pentacyclic triterpenoids, named centellasaponin I ( 1 ), centellasaponin J ( 2 ), and centellasaponin E ( 3 ), together with three known compounds, were isolated from the whole plants of Centella asiatica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D‐ and 2D‐NMR and HR‐MS experiments, and by comparison with literature data. 相似文献
999.
Elastic and Wearable Wire‐Shaped Lithium‐Ion Battery with High Electrochemical Performance 下载免费PDF全文
Jing Ren Ye Zhang Wenyu Bai Xuli Chen Zhitao Zhang Xin Fang Wei Weng Dr. Yonggang Wang Prof. Huisheng Peng 《Angewandte Chemie (International ed. in English)》2014,53(30):7864-7869
A stretchable wire‐shaped lithium‐ion battery is produced from two aligned multi‐walled carbon nanotube/lithium oxide composite yarns as the anode and cathode without extra current collectors and binders. The two composite yarns can be well paired to obtain a safe battery with superior electrochemical properties, such as energy densities of 27 Wh kg?1 or 17.7 mWh cm?3 and power densities of 880 W kg?1 or 0.56 W cm?3, which are an order of magnitude higher than the densities reported for lithium thin‐film batteries. These wire‐shaped batteries are flexible and light, and 97 % of their capacity was maintained after 1000 bending cycles. They are also very elastic as they are based on a modified spring structure, and 84 % of the capacity was maintained after stretching for 200 cycles at a strain of 100 %. Furthermore, these novel wire‐shaped batteries have been woven into lightweight, flexible, and stretchable battery textiles, which reveals possible large‐scale applications. 相似文献
1000.
Flexible and Stretchable Lithium‐Ion Batteries and Supercapacitors Based on Electrically Conducting Carbon Nanotube Fiber Springs 下载免费PDF全文
Ye Zhang Wenyu Bai Dr. Xunliang Cheng Jing Ren Dr. Wei Weng Peining Chen Xin Fang Zhitao Zhang Prof. Huisheng Peng 《Angewandte Chemie (International ed. in English)》2014,53(52):14564-14568
The construction of lightweight, flexible and stretchable power systems for modern electronic devices without using elastic polymer substrates is critical but remains challenging. We have developed a new and general strategy to produce both freestanding, stretchable, and flexible supercapacitors and lithium‐ion batteries with remarkable electrochemical properties by designing novel carbon nanotube fiber springs as electrodes. These springlike electrodes can be stretched by over 300 %. In addition, the supercapacitors and lithium‐ion batteries have a flexible fiber shape that enables promising applications in electronic textiles. 相似文献