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In this study, a novel half-sandwich phosphinesulfonate cobaltic complex (Co(dppbsa)) was prepared and characterized, which surprisingly enabled the chemoselective N,N-dimethylation of nitroaromatics with CO2 using NaBArF4 as the promotor and a combination of PhSiH3 and Et3SiH as the reductant. Further studies demonstrated that the catalytic activity for reduction of nitroaromatics and CO2 could be modulated, respectively, by using a specific structure and composition of hydrosilanes. The semi-reduction products nitrosoarene and silyl formate are the key intermediates affording the most efficient C–N coupling for the N,N-dimethylation of nitroaromatics with CO2. [ABSTRACT FROM AUTHOR]

Used Monte Carlo simulation to compare the relative measurement efficiency of polytomous modeling and dichotomous modeling under different scoring schemes and termination criteria. Results suggest that polytomous computerized adaptive testing (CAT) yields marginal gains over dichotomous CAT when termination criteria are more stringent. Discusses conditions under which polytomous CAT cannot prevent the nonuniform gain in test information. (SLD)

One‐step catalytic synthesis of methyl acrylate from methyl acetate and trioxane, with 90.7% yield and 91.8% selectivity, was realized at 10–25°5. NMR analysis confirmed the ester enolization with generation of [i‐Pr2EtN‐H]+[TfO]− in the presence of i‐Pr2EtN and Bu2BOTf, which was affected by solvent and base. The depolymerization of trioxane into formaldehyde was catalyzed by Bu2BOTf. The in‐situ catalytic mechanism and efficiency of [i‐Pr2EtN‐H]+[TfO]− was determined and analyzed. Mechanism‐based kinetic and thermodynamic studies were conducted for better understanding of this route. Also the primary process design and product separation simulation were carried out. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1359–1372, 2018 [ABSTRACT FROM AUTHOR]

This article examines changes in the relations between Nationalist China, the Soviet Union, and Japan after 1931. In particular, it analyzes the Nationalist Government’s response to the dilemma posted by their changers. Japan’s strategy was to invade China in preparation for World War II. Hence, how to avoid becoming the first sacrifice in the war was foremost in the minds of Chinese leaders, including Chiang Kai-shek. China recognized the necessity of preparing for war in 1935 to 1937, so Chiang started to promote military cooperation with the Soviet Union and making a treaty. Therefore, China and the Soviet Union signed the Sino-Soviet Non-Aggression Pact in 1937 as a result of this cooperation. [ABSTRACT FROM AUTHOR]

Objective To observe the chemotaxis of glioma cell line U87, U251 and T98G to U937. Methods We Subcultured U87, U251, T98G and U937 cells in vitro, used Transwell to observe the chemotaxis of three kinds of glioma cell line (U87, U251 and T98G) to U937. Results By Transwell method, we got the white blood cell count, compared with control group, the chemotaxis of three kinds of glioma cell line to U937 was apparently higher (P <0.05) . The chemotaxis of U87 to U937 is apparently higher than U251 to T98G (P < 0.05) . The chemotaxis of U251 and T98G to U937 had no statistical differences (P>0.05) . Conclusion U87, U251 and T98G can accelerate U937 cell migration, the chemotactic activity of U87 is more obvious. [ABSTRACT FROM AUTHOR]

Objective To evaluate the marginal microleakage of porcelain-fused-to-metal crown using four diffe-rent cements. Methods Sixteen porcelain-fused-to-metal crowns were built and randomly divided into 4 group, luted onto standard prepared human forward molars using four different cements (glass ionomer cement, resin-modified glass ionomer cement, PanaviaF, Super-Bond C&B adhesive luting system). After temperature cycling test, all the crowns were then submerged in 2% fuchsin for 24 h. The marginal microleakage at tooth cement interfaces was observed using light stereomicroscopy and evaluated in classification index. The marginal microleakage grade of 4 groups were analyzed by SPSS 13.0. Results The PanaviaF demonstrated the least marginal microleakage, Super-Bond C&B adhesive luting system, resin-modified glass ionomer cement showed an intermediate level of marginal microleakage, glass iono-mer cement was associated with severe marginal microleakage (total, %2=157.60, P<0.01; among the different groups, P<0.05). Conclusion Adhesive resin luting system which is the first selection in clinical is better than glass ionomer cement and is good at porcelain-fused-to-metal crown. [ABSTRACT FROM AUTHOR]

Biodiesel, derived from vegetable oil via hydrotreating, is becoming a promising alternative energy. Novel Ni–Mo–W/γ-Al 2 O 3 –ZSM-5 catalysts were developed and firstly applied in palm oil hydrogenation process. The catalysts were prepared by extrusion method and characterized by XRD, SEM, TEM, BET, NH 3 –TPD, and H 2 –TPR. The influences of acidity on the activity, selectivity, and stability of catalysts were systematically studied. The mechanisms of deoxygenation and isomerization were discussed. The catalyst Ni–Mo–W (5 wt.%–5 wt.%–15 wt.%)/γ-Al 2 O 3 –ZSM-5 (85 wt.% − 15 wt.%) was confirmed as the optimum one. Finally, the key reaction parameters such as reaction temperature, pressure, liquid hourly space velocity and H 2 /oil volume ratio were optimized. The hydrogenation reaction path of palm oil was also proposed. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the marginal microleakage of porcelain-fused-to-metal crown using four different cements., Methods: Sixteen porcelain-fused-to-metal crowns were built and randomly divided into 4 group, luted onto standard prepared human forward molars using four different cements (glass ionomer cement, resin-modified glass ionomer cement, PanaviaF, Super-Bond C&B adhesive luting system). After temperature cycling test, all the crowns were then submerged in 2% fuchsin for 24 h. The marginal microleakage at tooth cement interfaces was observed using light stereomicroscopy and evaluated in classification index. The marginal microleakage grade of 4 groups were analyzed by SPSS 13.0., Results: The PanaviaF demonstrated the least marginal microleakage, Super-Bond C&B adhesive luting system, resin-modified glass ionomer cement showed an intermediate level of marginal microleakage, glass ionomer cement was associated with severe marginal microleakage (total, Chi2 = 157.60, P < 0.01; among the different groups, P<0.05)., Conclusion: Adhesive resin luting system which is the first selection in clinical is better than glass ionomer cement and is good at porcelain-fused-to-metal crown.

The polymorphism distributions of 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, and FGA) were investigated in a Tibetan population by multiplex PCR amplification using five fluorochromes (6FAM, VIC, NED, PET, LIZ). Gene frequency, discrimination power (DP), heterozygosity (H), polymorphism information content (PIC) and probability of paternity exclusion (EPP) were calculated, and all loci were tested for Hardy-Weinberg equilibrium. Results indicate that the gene frequency of these 15 STR loci is in Hardy-Weinberg equilibrium. The DP is at 0.7555-0.9602, H is at 0.5651-0.8530, PIC is at 0.5528-0.8456, and EPP is at 0.3811-0.8549. Cumulative DP of the 15 STR is 0.99999999, and cumulative EPP is 0.999999997. Therefore, these 15 STR loci can be used as genetic markers of Tibetan populations in anthropological studies, linkage analysis of genetic diseases, individual identification and paternity testing in forensic medicine.