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Chinese Chemical Letters 2022年第1期33卷 234-238页

作者： Pengyu Wu chun cai Chemical Engineering College Nanjing University of Science and TechnologyNanjing 210094China

Catalytic hydrodeoxygenation(HDO)is one of the most effective methods to upgrade the oxygen-containing compounds derived from coal tar to valuable ***,an efficient bimetallic catalyst Pt_(1)Ni_(4)/MgO was prepared and applied in the HDO of dibenzofuran(DBF).High yield(95%)of the desired product bicyclohexane(BCH)was achieved at 240℃and 1.2 MPa of H_(2).Superior catalytic performance could be ascribed to the"relay catalysis"of Pt sites and Ni sites,and the reaction pathway is proposed as ***-up experiment and recyclability test were also performed,which demonstrated the recyclability and promising potential application of Pt_(1)Ni_(4)/MgO.

关键词： Hydrodeoxygenation Dibenzofuran Bicyclohexane Bimetallic catalyst Relay catalysis

Early changes in white blood cell,C-reactive protein and procalcitonin levels in children with severe multiple trauma

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World Journal of Emergency Medicine 2022年第6期13卷 448-452页

作者： cai-fang Xu Ming-chao Huo Jin-hui Huang chun-feng Liu Wei Xu The Pediatrics Department Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Critical Care Medicine Shanghai Children’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200062China

BACKGROUND:To analyze early changes in white blood cells(WBCs),C-reactive protein(CRP)and procalcitonin(PCT)in children with multiple trauma,before secondary inflammation ***:This single-center retrospective study collected data from patients with blunt traumatic injury admitted to the pediatric intensive care unit(PICU).According to the prognostic outcome of 28 d after admission to the PICU,patients were divided into survival group(n=141)and non-survival group(n=36).Characteristics between the two groups were *** operation characteristic(ROC)curve analysis was conducted to evaluate the capacity of different biomarkers as predictors of ***:The percentages of children with elevated WBC,CRP,and PCT levels were 81.36%,31.07%,and 95.48%,*** in the non-survival group presented a statistically significantly higher injury severity score(ISS)than those in the survival group:37.17±16.11 vs.22.23±11.24(t=6.47,P<0.01).WBCs were also higher in non-survival group than in the survival group([18.70±8.42]×109/L vs.[15.89±6.98]×109/L,t=2.065,P=0.040).There was no significant difference between the survival and non-survival groups in PCT or *** areas under the ROC curves of PCT,WBC and ISS for predicting 28-day mortality were 0.548(P=0.376),0.607(P=0.047)and 0.799(P<0.01),***:Secondary to multiple trauma,PCT levels increased in more patients,even if their WBC and CRP levels remained ***,early rising WBC and ISS were superior to PCT at predicting the mortality of multiple trauma patients in the PICU.

关键词： Pediatric Procalcitonin Injury severity score Multiple trauma

A new nonparametric stability test with an application to major Chinese macroeconomic time series

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 1-16页

作者： cai Nan cai Zong-wu fang Ying The Wang Yanan Institute for Studies in Economics MOE Key Laboratory of Econometrics (Xia- men University) Fujian Provincial Key Laboratory of Statistical Science Xiamen University Department of Mathematics and Statistics University of North Carolina at Charlotte

In this paper, we propose a new test for testing the stability in macroeconomic time series, based on the LASSO variable selection approach and nonparametric estimation of a time-varying model. The wild bootstrap is employed to obtain its data-dependent critical values. We apply the new method to test the stability of bivariate relations among 92 major Chinese macroeconomic time series. We find that more than 70% bivariate relations are significantly unstable.

关键词： LASSO stability test time-varying coefficients model wild bootstrap.

Design and analysis of spiral bevel gears with seventh-order function of transmission error

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Chinese Journal of Aeronautics 2013年第5期26卷 1310-1316页

作者： Su Jinzhan fang Zongde cai Xiangwei Key Laboratory of Road Construction Technology and Equipment Ministry of EducationChang’an University School of Mechanical Engineering Northwestern Polytechnical University

This paper proposes a new approach to mial function of transmission error （TE） for spiral design and implement a seventh-order polyno- bevel gears with an aim to reduce the running vibration and noise of gear drive and improve the loaded distribution of the tooth. Based on the constraint conditions of predesigned seventh-order polynomial function curve and the theory of linear algebra, the polynomial coefficients of the seventh-order polynomial function of transmission error can be obtained. By applying a method named reverse tooth contact analysis, the modified roll coefficients as well as parts of machine-tool settings for the face-milling of spiral bevel gears can be individually determined. Therefore, a predesigned seventh-order polynomial function of transmission error for spiral bevel gears can be obtained by the modified roll with high-order coef- ficients, and comparisons of the seventh-order polynomial and parabolic functions of transmission error are also performed. The achievement of spiral bevel gears with the seventh-order function of transmission error can be accomplished on a universal Cartesian-type hypoid gear generator or a numerically controlled cradle-style hypoid gear generator due to its simple generating motion of axes of the cradle and the work piece. The results of a numerical example show that the bending stresses of the tooth of seventh-order are less than those of a parabolic one, while the contact stresses remain almost eouivalent.

关键词： Loaded tooth Modified roll Spiral bevel gear Tooth contact analysis Transmissions

Trifluoromethylation of Carbonyl Compounds with Sodium Trifluoroacetate

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Chinese Chemical Letters 2005年第10期16卷 1313-1316页

作者： Ying CHANG chun cai School of Chemical Engineering Nanjing University of Science and Technology Nanjing 210094

In the presence of copper （I） halide as catalyst, a variety of carbonyl compounds could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields.

关键词： Trifluoromethylation sodium trifluoroacetate carbonyl compounds aldehydes.

Gastric body diaphragm-like stricture as a rare complication of nonsteroidal anti-inflammatory drugs

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World Journal of Gastroenterology 2013年第23期19卷 3703-3706页

作者： Li-Li Wu Yun-Sheng Yang Feng-chun cai Shu-fang Wang Department of Gastroenterology and Hepatology Chinese People's Liberation Army General Hospital

Increased risk due to nonsteroidal anti-inflammatory drugs (NSAIDs) therapy has been observed in patients. Although diaphragm-like stricture in the small bowel and colon induced by NSAIDs therapy has been rarely reported, gastric body diaphragm-like stricture has not been reported. We describe the first case of gastric body diaphragm-like stricture due to NSAIDs in a 44-year-old male patient who was successfully treated by an endoscopic approach to avoid complicated surgery. This case highlights new insight into the disadvantages of NSAIDs and provides new data for future clinical studies.

关键词： Gastric Gastroscopy Diaphragm Stricture Nonsteroidal anti-inflammatory drug

Perfect Matching in k-partite k-graphs and 3-uniform HM-bipartite Hypergraphs

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 636-641页

作者： chun-qiu fang Mei LU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

Let H=(V,E)be an n-balanced k-partite k-graph with partition classes V1,...,*** for every legal(k-1)-tuple f contained in V\V1 and for every legal(k-1)-tuple g contained in V\Vk such that f∪g■E(H),we have d(f)+d(g)≥n+*** this paper,we prove that under this condition H must have a perfect *** result of this paper is about the perfect matching in 3-uniform hm-bipartite *** G be a 3-uniform hm-bipartite hypergraph with one of whose sides V1 has the size n,the another side V2 has size 2 *** for all the legal 2-tuple f with|f∩V1|=1 and for all the legal 2-tuple g with|g∩V1|=0,we have d(f)≥n-2 and d(g)>n/2,then G has a perfect matching.

关键词： Perfect matching k-partite k-graph hm-bipartite hypergraph

Effect of vacuum annealing on the characteristics of composite pellets containing DBSA-doped polyaniline and Fe nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 236-241页

作者： Qing Wu Hong Qiu chun-ying fang Kun fang School of Applied Science University of Science and Technology Beijing Beijing 100083 China Material Research Center Beijing Institute of Science and Technology Beijing 100081 China

The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellets were annealed in vacuum at 443,493,543, and 593 K for 60 and 120 min. The conductivity of the pellet increases markedly with increasing the annealing temperature up to 493 K, and then decreases with further increasing the annealing temperature. When the pellet was annealed at 493 K for 60 min, the increment of conductivity reaches a maximum value, and the conductivity is 2.6 times as large as that of the pellet unannealed. The conductivities of the pellets annealed under the conditions of 543 K/120 min, 593 K/60 min, and 593 K/120 min are lower than the conductivity of the pellet unannealed. For all the pellets, the variation in conductivity with temperature reveals that the charge transport mechanism can be considered to be 1-D variable-range-hopping （1-D VRH）. The composite pellet shows a magnetic hysteresis loop independent of the annealing condition. The saturation magnetization is about 5.4×10^4 emu/kg. The saturation field and the coercivity are estimated to be 4.38×10^5 and 3.06×10^4 A/m, respectively. The crystalline structure ofFe nanoparticles in the composites does not change with the annealing condition. The annealing condition cannot destroy the polymer backbones.

关键词： doped polyaniline dodecylbenzene sulfonic acid (DBSA) Fe nanoparticles vacuum annealing structure conductivity magnetization

Design and Analysis for a Three-Rotational-DOF Flight Simulator of Fighter-Aircraft

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 48-59页

作者： Chang-chun Zhou Yue-Fa fang Robot Research Center Beijing Jiaotong University

Most of researchers focused on traditional six degrees of freedom(DOF) Stewart flight simulator,which can not be adaptive in fighter?aircraft flight simulator. A three rotational DOF flight simulator of fighter?aircraft based on dou?ble parallel manipulator and hybrid structure is presented. The flight simulator is composed of two identical 3?RRS(revolute?revolute?spherical) spherical parallel manipulators and one cabin,called Twins. The cabin has an additional independent DOF for 360° continuous rotation,so it can be applied as a flight simulator for a fighter?aircraft to achieve spin maneuvering. Because of the introduction of the hybrid structure and double parallel manipulator of themechanism,the redundancy exists with respect to both kinematics and actuation. Kinematics is carried out and Jaco?bian matrix is established by means of screw theory. The inverse kinematics is given out by the analytical method. 64 groups inverse solutions are showed in a table by permutation. Forward kinematics is solved by an e ectively numeri?cal method. The forward numerical method is realized based on the analytically inverse kinematics and Jacobian matrix. The numerical examples show that the forward numerical method can be used in real?time control. The rollingmotion is considered in forward kinematics and a numerical example is given out. The proposed flight simulator can spin and there are three rotational DOF with a hybrid structure so that the novel flight simulator can be used in the field of the fighter?aircraft for pilots to train.

关键词： Parallel manipulator Hybrid mechanisms Actuation redundancy Flight simulator Kinematics Screw theory Jacobian matrix

Characterization of eating quality and starch properties of two Wx alleles japonica rice cultivars under different nitrogen treatments

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Journal of Integrative Agriculture 2020年第4期19卷 988-998页

作者： HUANG Shuang-jie ZHAO chun-fang ZHU Zhen ZHOU Li-hui ZHENG Qing-huan WANG cai-lin Institute of Food Crops Jiangsu Academy of Agricultural Sciences/Jiangsu High Quality Rice R&D Center/Nanjing Branch of China National Center for Rice ImprovementNanjing 210014P.R.China College of Tea Science Xinyang Agriculture and Forestry UniversityXinyang 464000P.R.China Agri-Tech Extension Center of Wancheng District Nanyang 473000P.R.China

To understand the effect of nitrogen(N) fertilizer on rice(Oryza sativa L.) eating and cooking quality(ECQ). Here, we investigated the ECQ attributes, physicochemical foundation of ECQ, and amylopectin fine structure of two Waxy(Wx) alleles japonica rice cultivars Nanjing 9108(NJ9108) and Huaidao 5(HD5) under four N rates(0, 150, 300, and 450 kg ha^-1). Sensory and pasting properties of the two cultivars varied depending on N rates. Compared with the control(0 kg ha^-1), the overall eating quality and sensory value were significantly decreased under the N rates of 300 and 450 kg ha^-1. Further, conventional descriptive analysis showed that the stickiness and retrogradation of cooked rice were significantly decreased. These results indicated that application of N fertilizer seems to affect the texture of cooked rice, causing it to be less sticky, lowering its retrogradation, and consequently reducing its palatability. Results from rapid visco analyzer(RVA) revealed that the peak and breakdown viscosities significantly decreased, while the setback viscosity and peak time increased under the N rates of 300 and 450 kg ha^-1. However, no significant difference was observed when the N rate was 150 kg ha^-1, indicating that less N fertilization can maintain rice ECQ. As the N rate increasing, protein content increased, whereas apparent amylose content, starch content, and gel consistency almost unchanged. Interestingly, compared with the control, under N treatments, the percentage of short amylopectin branches in NJ9108 was decreased, but increased in HD5, as controlled by amylopectin synthesis-related genes. Notably, SSI and BEIIb were down-regulated in NJ9108, whereas BEIIb was up-regulated in HD5. Thus, the palatability of both rice cultivars was significantly decreased under excessive N fertilization as a consequence of reduced stickiness and retrogradation of the cooked rice, which might have resulted from an elevated protein content and altered amylopectin fine struc

关键词： rice(Oryza sativa L.) nitrogen fertilizer eating and cooking quality amylopectin fine structure