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| 1 | Athabasca油砂沥青中重组分的分子模拟显示文摘利用分子模拟技术对加拿大Athabasca油砂沥青超临界萃取分馏残渣组分的化学分子结构进行了研究 ,首先选用长度不同的桥链构建了其三维平均结构 ,然后采用分子力学 (MM)和分子动力学 (MD)方法得到能量最低也即最稳定的构象 .研究发现 ,即使分子的二维结构相同 ,其三维结构差别也很大 ,由此可见仅用二维模型来表征重质油大分子的结构和物理化学性质远远不够 .另外 ,分子模拟还可以预测沥青质残渣中最有可能存在的桥链长度 .Athabasca沥青残渣组分中长度为C5到C7的桥链存在的可能性最大 ,而C1和C2桥链则由于其总能量相对较高 。 | 高金森 徐春明 Luba S.KOTLYAR Keng H.CHUNG | 2003 | 化工学报2003，54，1： | 14 |
| 2 | 用于制备聚氨酯纳米复合物的高岭石粒子的表征(英文)显示文摘Clay such as kaolinite, is commonly used as an additive to modify the thermal properties of polymer. In this paper, the morphology, composition, shape and structure of kaolinite was characterized by various advanced techniques. The TEM/ EDX data showed that the kaolinite had a larger particle size and a Si/Al ratio of 1.8. The individual particle of kaolinite was a single crystalline. TEM also showed that these particles were always stacked together due to the presence of electrostatic cohesive energy and hydrogen bond between plaletes. The PAS FTIR spectra showed that no absorbance of hydroxyl group for hydration water in hydrogen bond region or at 1650cm- 1 was observed at room temperature. It meant a little ability to adsorb water for kaolinite particle. Kaolinite clay also showed no change for its PAS FTIR spectra with increasing temperature. The TGA results revealed that kaolinite almost doesn′ t lose weight at 60℃ due to loss of dehydration of absorbed water, however, it will decomposed around 510℃ and lose its hydroxyl functional group in the form of water (dehydroxylation). The result is consistent with that of PAS FTIR analysis. This suggests that the structural hydroxyl group on the surface of individual kaolinite clay particle is very stable below 500℃ , and the kaolinite composed polymer could be got by the reaction of its stable structural hydroxyl group with isocynate group of polyurethane prepolymer. | 李再峰 王义银 Luba S.Kotlyar Keng H.Chung | 2003 | 无机化学学报2003，19，11： | 2 |
| 3 | Prevalence of levator ani muscle injury in Chinese women after first delivery显示文摘 | S. S. C.Chan R. Y. K.Cheung A. K. W.Yiu L. L. L.Lee A. W. L.Pang K. W.Choy T. Y.Leung T. K. H.Chung | 2012 | Ultrasound Obstet Gynecol2012，，6： | 1 |
| 4 | Ion exchange characteristics of palladium and ruthenium from a simulated radioactive liquid waste显示文摘 | S.H.Lee H.Chung | | 0，，： | 1 |
| 5 | Computed tomography‐based tissue‐engineered scaffolds in craniomaxillofacial surgery显示文摘 | M. H.Smith C. L.Flanagan J. M.Kemppainen J. A.Sack H.Chung S.Das S. J.Hollister S. E.Feinberg | 2007 | Int. J. Med. Robotics Comput. Assist. Surg2007，，3： | 1 |
| 6 | Subchronic Oral Toxicity of Pyridostigmine Bromide in Rats显示文摘This study evaluated the oral toxicity of pyridostigmine bromide in Sprague-Dawley rats when administered for 13 weeks by daily gavage. Groups of 10 rats/sex received doses of 0, 5, 15, 30, or 60 mg/kg/day. Toxicity was limited to exaggerated cholinergic stimulation at doses of 15 mg/kg/day or greater. Significant findings included tremors and inhibition of RBC acetylcholinesterase. Thus, 5 mg/kg/day of pyridostigmine bromide appears to be the no observed toxic effect level under the conditions of the present investigation. | B.S.LEVINE R.LONG H.CHUNG | 1991 | Biomedical and Environmental Sciences1991，4，3： | 1 |
| 7 | Association of TXNDC5 gene polymorphisms and susceptibility to nonsegmental vitiligo in the Korean population显示文摘 | K‐H.Jeong M‐K.Shin Y‐K.Uhm H‐J.Kim J‐H.Chung M‐H.Lee | 2010 | British Journal of Dermatology2010，，4： | 1 |
| 8 | Characterization of Ultra Fine Solids(BS) in Athabasca Bitumen显示文摘The ultra fine (<200 nm) inorganic solids (BS) were separated from bitumen which was washed by toluene and centrifugated at 2000 rpm. The result of PAS FTIR and image of TEM showed that the structure of BS particles was smiliar to that of kaolinite clay. On the surface of BS, both toluene insoluble organic matter and structural OH group are detected at the same time. The surface characteristics imparted a bi-wettable nature to the BS. As a result, the BS is able to stabilize fine water emulsion in the bitumen phase. The organic matter associated with BS is a possible factor of the fouling on catalyst and equipment. | 李再峰 Judy KUNG 涂云 Luba S.Kotlyar Keng H.Chung | 2004 | Chinese Journal of Structural Chemistry2004，23，7： | 1 |
| 9 | Factors that affect heart rate variability following acute resistance exercise:A systematic review and meta-analysis显示文摘Background:There is controversial evidence regarding the effect of acute resistance exercise(ARE) on heart rate variability(HRV) parameters,which indicates the activities of the cardiac autonomic nervous system.The aim of this study was to perform a systematic review and meta-analysis of the literature on the effect of ARE on HRV parameters and identify its possible moderating factors.Methods:The PubMed-Medline,Web of Science,SPORTDiscus,and Cochrane Library databases were searched.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) declaration was followed,and the methodological quality of the studies was evaluated.The level of significance was set at p≤0.05.Twenty-six studies met the inclusion criteria.Main effect analyses between pre-and post-test interventions demonstrated an increase in normalized units low frequency(p <0.001;standardized mean difference(SMD)=0.78;95% confidence interval(95%CI):0.46-1.11) and low frequency/high frequency ratio(p <0.001;SMD=0.82;95%CI:0.64-0.99) and a decrease in standard deviation of the normal-to-normal(NN)interval(p <0.001;SMD=-0.58;95%CI:-0.85 to-0.30),root mean square of the successive differences(p <0.001;SMD=-1.01;95%CI:-1.29 to-0.74),and normalized units high frequency(p <0.001;SMD:-1.08;95%CI:-1.43 to-0.73) following ARE in healthy individuals range:15 ± 1 to 48 ± 2 years;mean ± SD).Results:There were differences between the subgroups in the number of sets used in an exercise(p=0.05) for root mean square of the successive differences,as well as for exercise intensity(p=0.01) and rest between sets(p=0.05) for normalized units high frequency.Interestingly,there were differences between the subgroups in training volume for root mean square of the successive differences(p=0.01),normalized units high frequency(p=0.003) and normalized units low frequency(p=0.02).Conclusion:Overall,there was a withdrawal of cardiac parasympathetic and activation of cardiac sympathetic modulations following ARE,and these changes were greater with higher training volume ~30 min after ARE in healthy individuals.Furthermore,the number of sets,intensity,and rest between sets affected HRV parameters.However,gender,body mass index,and training status did not influence the changes in HRV parameters as a response to ARE. | Sajith U.Marasingha-Arachchige JacoboÁ.Rubio-Arias Pedro E.Alcaraz Linda H.Chung | 2022 | Journal of Sport and Health Science2022，11，3： | 0 |
| 10 | Molecular composition of naphthenic acids in a Chinese heavy crude oil and their impacts on oil viscosity显示文摘Most heavy crude oils underwent biodegradation and generated a significant amount of naphthenic acids. Naphthenic acids are polar compounds with the carboxylic group and are considered as a major factor affecting the oil viscosity. However, the relationship between the molecular composition of naphthenic acids and oil viscosity is not well understood. This study examined a “clean” heavy oil with low contents of heteroatoms but had a high content of naphthenic acids. Naphthenic acids were fractionated by distillation and caustic extraction. The molecular composition was characterized by high-resolution Orbitrap mass spectrometry. It was found that the 2- and 3-ring naphthenic monoacids with 15–35 carbon atoms are dominant components of the acid fractions;the caustic extraction is capable of isolating naphthenic acids with less than 35 carbons, which is equivalent to the upper limit of the distillable components, but not those in the residue fraction;the total acid number of the heavy distillates is higher than that of the residue fraction;the viscosity of the distillation fraction increases exponentially with an increased boiling point of the distillates. Blending experiments indicates that there is a strong correlation between the oil viscosity and acids content, although the acid content is only a few percent of the total oil. | Qian-Hui Zhao Shuai M Jian-Xun Wu Wei-Feng Chang Sheng-Fei Zhang Xin-Ge Sun Bing Zhou Zeng-Min Lun Keng H.Chung Quan Shi | 2023 | Petroleum Science2023，20，2： | 0 |
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