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101.
The enthalpy and conformational volume changes in the photolyses of carboxy-hemoglobin (HbCO) of human, bovine, pig, horse and rabbit are investigated by photoacoustic calorimetry. Considering the time scales of the exciting laser pulse and the receiving ultrasound transducers (PVDF films and PZT ceramics), as well as the reaction lifetimes in the photolysis processes of HbCO, the measured results are related to the geminate recombination and tertiary relaxation in photolyses of HbCO. Moreover, the quantum yields of the five mammals are also measured by laser pump-probe technique. The results show that the dynamic parameters, such as enthalpy and conformational volume changes, differ between the processes of the geminate recombination and tertiary relaxation. Also, the dynamic parameters differ among the five mammals although some of them may be consistent with each other.  相似文献   
102.
A novel reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides was performed in the presence of silver nitrate or triflate.Conjugated vinyl sulfones as dramatic products were obtained in moderate yields and with Z-selectivity.A free radical mechanism has been proposed to account for the formation of the products.  相似文献   
103.
We demonstrate that an arbitrary Bell state can be achieved in a two qubit anisotropic Heisenberg XY chain via Lyapunov control. During the whole process, we only need to apply an external field along a given direction to a single qubit. This control strategy is effective for all initial states in the four-dimensional Hilbert space where the target state is asymptotically stable. The effects of imperfections on the fidelity for the target state such as Gaussian leakage of local control and localized dephasi...  相似文献   
104.
A graph is said to be s-arc-regular if its full automorphism group acts regularly on the set of its s-arcs. In this paper, we investigate connected cubic s-arc-regular Cayley graphs of finite nonabelian simple groups. Two suffcient and necessary conditions for such graphs to be 1- or 2-arc-regular are given and based on the conditions, several infinite families of 1-or 2-arc-regular cubic Cayley graphs of alternating groups are constructed.  相似文献   
105.
An efficient and mild synthesis of 2-(guaiazulen-1-yl)furans,starting from easily accessible 1-(3-aryl-2-cyanopropenoyl) guaiazulenes,tributylphosphine and acyl chlorides,is described.The strategy employs the intramolecular Wittig protocol as a key step to append the crticial furan ring,leading to the highly functional furans in good yields.  相似文献   
106.
毛细管气相色谱法测定热不稳定有机磷农药辛硫磷   总被引:11,自引:0,他引:11  
顾明松  罗毅 《色谱》1995,13(6):470-469
The thermo-labile organophosphorous pesticide Phoxim was determined by capillary gas chromatographywith flame phototnetric detector. When high linear velocity H_2(>200cm/s) was used as carrier gas,the thermo-decomposition of Phoxim was considerably reduced.The most important gas chromatography conditions,injectortempereture and column head pressure,were studied.The thermo-decomposition preducts were identified by gaschromatography-mass spectrometry.  相似文献   
107.
树脂NKY对染料活性艳蓝KN-R的吸附特性   总被引:4,自引:0,他引:4  
本文系统地研究了树脂NKY对染料活性艳蓝KN-R的静态吸附性能,并与其它提取分离有机物的某些商品化吸附剂进行了比较。结果表明,树脂NKY吸附KN-R具有很好的效果,吸附速率由液膜扩散控制,吸附等温曲线由三参数方程非线性回归求出的常数可计算△G^0,由温度对吸附的影响求得的△H^0说明吸附过程中吸热的而且是自发进行的。  相似文献   
108.
A New Perylenequinone from Hypomyces sp.   总被引:4,自引:0,他引:4  
Some metabolites of fungi and plants containing perylenequinones have been used as folk medicine for the treatment of many diseases1,2. A filamentous fungus, Ascomy-cetes Hypocreaceae Hypomyces (Fr.) Tul. sp., was found from the northwestern mountains of Yunnan Province, and cultured successfully in the laboratory. A new perylenequinone, named hypomycin A (1), was isolated from its mycelia. In this paper the structure elucidation of 1 was described. Figure 1 The structure of compound 1 Fig…  相似文献   
109.
几种树脂对西红花糖苷的吸附性能的研究   总被引:3,自引:0,他引:3  
本文系统研究了硅胶和几种国产吸附树脂对西红花提取物溶液的吸附与洗脱性能,包括树脂的筛选,洗脱剂的选择,并研究了pH,温度和西红花提取物的浓度对西红花提取在SZ-1吸附树脂上的吸附影响,结果表明,SZ-1吸附树脂对西红花提取物的吸附能力较强,洗脱能力为最好,其吸附性能和洗脱性能均优于常用色谱固定相硅胶,SZ-1吸附树脂的静态吸附容量为1.04g/g,动态吸附容量为0.5-0.6g/g,洗脱率可达98%以上,且吸附速度快,易于洗脱和再生。  相似文献   
110.
7,3′-二甲氧基-4′,5′-次乙二氧基黄烷酮的合成   总被引:1,自引:0,他引:1  
汪秋安  张春香  麻秋娟 《合成化学》2005,13(1):67-69,72
以香草醛和问苯二酚为原料,经7步反应合成了新的苯并二氧六环新木脂素黄酮类似物7,3′-二甲氧基-4′,5′-次乙二氧基黄烷酮,总收率16.1%,其结构经^1H NMR,IR和MS证实。  相似文献   
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