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81.
Sheng-Hung Wu Chu-Chin Hsieh Chung-Cheng Chiang Jao-Jia Horng Wei-Ping Pan Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2012,109(2):945-950
Volatile organic compounds (VOCs) and greenhouse gases are the main factors involved in pollution control and global warming. Various treatment methods involving incineration, adsorption, etc., have been employed to reduce VOCs and greenhouse gases concentration in the operating environment and atmosphere. Activated carbon, zeolite, silica gel, and alumina have been broadly used to adsorb pollutants in various industrial applications. Based on the promising effect of adsorption, we analyzed and identified the thermal phenomena of home-made zeolite using various instruments. The endothermic reaction under 100?°C of home-made zeolite was identified as steam adsorption, which is an important discovery. The optimal adsorption temperatures of home-made zeolite have been determined at 200?C550?°C. 相似文献
82.
Juan Li Guang‐Hui Zhao Dong‐Hui Zhou Hiromu Sugiyama Alasdair J. Nisbet Xiao‐Yan Li Feng‐Cai Zou Hai‐Long Li Lin Ai Xing‐Quan Zhu 《Electrophoresis》2012,33(18):2859-2866
In the present study, retrotransposon‐microsatellite amplified polymorphism (REMAP) was used to examine genetic variability among Schistosoma japonicum isolates from different endemic provinces in mainland China, using S. japonicum from Japan and the Philippines for comparison. Of the 50 primer combinations screened, eight produced highly reproducible REMAP fragments. Using these primers, 190 distinct DNA fragments were generated in total, of which 147 (77.37%) were polymorphic, indicating considerable genetic variation among the 43 S. japonicum isolates examined. The percentage of polymorphic bands (PPB) among S. japonicum isolates from mainland China, Japan, and the Philippines was 77.37%; PPB values of 18.42% and 53.68% were found among isolates from southwestern (SW) China and the lower Yangtze/Zhejiang province in eastern (E) China, respectively. Based on REMAP profiles, unweighted pair‐group method with arithmetic averages (UPGMA) dendrogram analysis revealed that all of the S. japonicum samples grouped into three distinct clusters: parasites from mainland China, Japan, and the Philippines were clustered in each individual clade. Within the mainland China cluster, SW China isolates (from Sichuan and Yunnan provinces) grouped together, whereas worms from E China (Zhejiang, Anhui, Jiangxi, Jiangsu, Hunan, and Hubei provinces) grouped together. These results demonstrated that the REMAP marker system provides a reliable electrophoretic technique for studying genetic diversity and population structures of S. japonicum isolates from mainland China, and could be applied to other pathogens of human and animal health significance. 相似文献
83.
C.-C. Chiang J.-C. Lee Y.-M. Chang C.-F. Chuang C.-M. Shu 《Journal of Thermal Analysis and Calorimetry》2009,96(3):759-763
Knowledge of material safety properties is critical for safe handing in the chemical process industries, especially for flammable
chemicals that might result in serious fires and explosions. This study investigated the flammability characteristics of methanol
under working conditions during the process. The targeted fire and explosion properties, like explosion limits (UEL and LEL),
vapor deflagration index (K
g), maximum explosion pressure (P
max), and maximum explosion pressure rise [(dP dt
−1)max], were deliberately obtained via a 20-L-Apparatus in 101 kPa (i.e., 760 mmHg/1 atm), 150 and 200 °C, along with various experimental
arrangements containing nitrogen (N2) or carbon dioxide (CO2) as inert component. Particularly, this study discussed and elucidated the inert influence on the above safety-related parameters
by two different inerting gases of N2 and CO2. The results indicated that adding an inert component to fuel–inert gas mixtures determined the decrease of explosion range
and flammability hazard degree. The results also demonstrated that CO2 possessed higher inerting capability than N2 in this study. 相似文献
84.
Three new phenanthrenes from Monomeria barbata Lindl 总被引:1,自引:0,他引:1
Ming Hui Yang Le Cai Mei Hong Li Xiang Hui Zeng Ya Bin Yang Zhong Tao Ding 《中国化学快报》2010,21(3):325-328
<正>Three new monophenanthrene compounds were isolated from an acetone extract of the tubers of Monomeria barbata Lindl. (Orchidaceae).Using spectroscopic methods,the structures of compounds 1-3 were determined as 1,4,7-trihydroxy-2-methoxy- 9,10-dihydrophenanthrene(1),1-(p-hydroxybenzoyl)-2-methoxy-4,7-dihydroxy-9,10-dihydrophenanthrene(2),1,3,8-tri(p-hydroxybenzyl) -4-methoxy-phenanthrene-4,7-diol(3).These compounds showed cytotoxicities on four tumor cell lines(HepG2, HL-60,Skov-3,A431). 相似文献
85.
86.
The dynamic behaviors of a SMIB power system are studied in this paper. A single modal equation is used to analyze the qualitative behaviors of the system. The famous equation of motion is called “swing equation”. The Lyapunov direct method is applied to obtain conditions of stability of the equilibrium points of the system. The bifurcation of the parameter dependent system is studied numerically. Besides, the phase portraits, the Poincaré maps, and the Lyapunov exponents are presented to observe periodic and chaotic motions. Further, the addition of periodic force and the feedback control are used to control chaos effectively. Finally, the chaotification problem of the SMIB power system is also issued. 相似文献
87.
Tien-Yuan Lu Chung-Cheng Chiang Sheng-Hung Wu Kuan-Chung Chen Shinn-Jou Lin Chia-Yuan Wen Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2013,114(3):1083-1088
In this study, the thermal hazard features of various lithium-ion batteries, such as LiCoO2 and LiFePO4, were assessed properly by calorimetric techniques. Vent sizing package 2 (VSP2), an adiabatic calorimeter, was used to measure the thermal hazards and runaway characteristics of the 18650 lithium-ion batteries under an adiabatic condition. The thermal behaviors of the lithium-ion batteries were obtained at normal and abnormal conditions in this study. The critical parameters for thermal hazardous behavior of lithium-ion batteries were obtained including the exothermic onset temperature (T 0), heat of decomposition (ΔH), maximum temperature (T max), maximum pressure (P max), self-heating rate (dT/dt), and pressure rise rate (dP/dt). Therefore, the result indicates the thermal runaway situation of the lithium-ion battery with different materials and voltages in view the of TNT-equivalent method by VSP2. The hazard gets greater with higher voltage. Without the consideration of other anti-pressure measurements, different voltages involving 3.3, 3.6, 3.7, and 4.2 V are evaluated to 0.11, 0.23, 0.88, and 1.77 g of TNT. Further estimation of thermal runaway reaction and decomposition reaction of lithium-ion battery can also be confirmed by VSP2. It shows that the battery of a fully charged state is more dangerous than that of a storage state. The technique results showed that VSP2 can be used to strictly evaluate thermal runaway reaction and thermal decomposition behaviors of lithium-ion batteries. The loss prevention and thermal hazard assessment are very important for development of electric vehicles as well as other appliances in the future. Therefore, our results could be applied to define important safety indices of lithium-ion batteries for safety concerns. 相似文献
88.
自1978年顺铂成功地被开发成癌症临床治疗药物以来,金属配合物作为小分子抗癌药物的开发成为人们的研究热点。其中,氮杂环卡宾能与多种过渡金属中心形成稳定的共价键,这种特殊的稳定性使得金属氮杂环卡宾配合物具有被开发成药物的潜能。近年来,金属氮杂环卡宾配合物被发现具有良好的抗癌活性,激发了广大无机药物化学研究者的研究热情。综合笔者课题组在金属氮杂环卡宾抗肿瘤配合物方面的前期研究,本文将对银、金、铑和铂氮杂环卡宾配合物的抗肿瘤活性及作用机制进行综述,以期为新型金属氮杂环卡宾抗肿瘤化合物的设计合成提供参考。 相似文献
89.
Jian‐Rong Luo Qing‐Yun Ma You‐Xing Zhao Tie‐Mei Yi Cheng‐Sen Li Jun Zhou 《中国化学会会志》2009,56(3):600-605
Some Miocene‐fossil wood of Pinus griffithii preserved as lignified wood in brown coal was found in an open coalmine in Xundian of Yunnan Province, China. To explore its chemical components, here we show the palaeophytochemical investigation of this Pliocene‐fossil wood of P. armandii, resulting in the isolation of 11 compounds ( 1–11 ) including one new compound named 3,3‐dimethoxy‐24‐ethyl‐cholestan ( 1 ) by liquid column chromatography. Furthermore, sixteen volatiles were detected from this fossil wood by gas chromatography‐mass spectrometry (GC‐MS). These structures of 11 compounds were elucidated by analysis of their MS, 1D and 2D‐NMR spectra, and comparison with published data. 相似文献
90.