Insight into Fundamental Rules of Phenylenediamines Selective Monoacylation by the Comparisons of Kinetic Characteristics in Microreactor

Xu Qilin,Liu Ji Ming,Yao Hongmiao,Zhao Jinyang,Wang Zhikuo,Liu Junli,Zhou Jiadi,Yu Zhiqun,Su Weike 대한화학회 2021 Bulletin of the Korean Chemical Society Vol.42 No.10

In this paper, the kinetics of acylation reaction of o-phenylenediamine/p-phenylenediamine and benzoic anhydride were determined in microreactors, respectively. A kinetic model was established, all kinetic parameters including reaction orders, reaction rate constants, pre-exponential factors, and activation energies were acquired. Validation experiments showed experimental data fit well with calculated data at different reactant concentrations and residence times. The comparisons of the reaction rate constants and activation energies were summarized to show the difference of chemical reactivities of phenylenediamines. According to the calculation of the kinetic model, the optimized reaction conditions were listed to meet the monoacylation selectivity equal to 97.0%.

The mutation of Scenedesmus obliquus grown in municipal wastewater by laser combined with ultraviolet

Xu Zhou,Wenbiao Jin,Song-fang Han,Xiaoye Li,Shu-Hong Gao,Chuan Chen,Guo-jun Xie,Renjie Tu,Qing Wang,Qilin Wang 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.6

Mutagenetic breeding is an efficient technique for the enhancement of lipid productivity from microalgae. In this study, oil-rich microalga Scenedesmus obliquus were treated by Laser-UV composite mutagenesis. Among the 35 mutant strains, X5 was primely screened. Afterwards, a twice UV mutagenizing was operated on X5, and the optimal mutant strain X5-H13 was obtained. The growth rate, dry weight, lipid yield and lipid content of X5-H13 were 0.698× 107 cells/mL·d, 0.99 g/L, 0.49 g/L and 48.8% while cultivated in municipal wastewater, respectively, which were increased by 45%, 58%, 109% and 32% than the original strain. The results of the subculture of repeated mutant showed that the biomass and lipid content of strain X5-H13 were up to 0.99 g/L and 48.8%. The growth of each generation was stable. Furthermore, the random amplified polymorphic DNA analysis indicated that the mutant strain X5-H13 was different from the starting strain, with their genetic similarity coefficient value of 0.815.

Effects of particle size of zero-valent iron (ZVI) on peroxydisulfate-ZVI enhanced sludge dewaterability

Xu Zhou,Hongyi Chen,Shu-Hong Gao,Songfang Han,Renjie Tu,Wei Wei,Chen Cai,Peng Liu,Wenbiao Jin,Qilin Wang 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.10

The advanced oxidization process has proven to be an effective conditioning technique for the improvement of sludge dewaterability. Zero-valent iron (ZVI) is often used as the catalyst of the oxidization process. This study applied ZVI with different particle sizes to the ZVI- peroxydisulfate reactions, and investigated their effects on the improvement of sludge dewaterability. It was found that ZVI particles with smaller sizes (100 and 400 meshes) led to slightly higher enhancement of sludge dewaterability (69.1%-72%) than the larger size particles (20-40 meshes) with the reduction rate of CST by 64%. However, after the treatment, the recycle rate of larger size ZVI particles was obviously higher than the small sizes ZVI particles: 98.3% vs. 87.6-89.7%. Different surface areas of the ZVI particles with different sizes might contribute to the phenomenon. For the small ZVI particles with the sizes of 100 and 400 meshes, no obvious differences of oxidization effects and the improvements of sludge dewaterability were found between them, which might be because an oxide layer could have been formed on the surface of fine ZVI particles and led to agglomeration. According to the economical analysis, the small particles (100 and 400 meshes) of ZVI were more economically favorable for the oxidative conditioning process with ZVI-peroxydisulfate than large ZVI particles (20-40 meshes).

Wind-induced response of open type hyperbolic-parabolic membrane structures

Junhao Xu,Yingying Zhang,Lanlan Zhang,Meng Wu,Yi Zhou,Ke Lei,Qilin Zhang 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.2

In this paper, the mechanical characteristics of the open type hyperbolic-parabolic membrane structure under wind load were investigated. First, the numerical simulation of a typical plane membrane structure was performed based on the Large-Eddy Simulation method. The accuracy of the simulation method was validated by the corresponding wind tunnel test results. Then, the wind load shape coefficients of open type hyperbolic-parabolic membrane structures are obtained from the series of numerical calculations and compared with the recommended values in the “Technical Specification for Membrane Structures (CECS 158: 2015). Finally, the influences of the wind directions and wind speeds on the mean wind pressure distribution of open type hyperbolic-parabolic membrane structures were investigated. This study aims to gain a better understanding of the wind-induced response for this type of structure and be useful to engineers and researchers.

Influence of Illumination with Xenon or Sulfur Lamp on Growth of Tomato Seedlings

Chen, Qilin,Yu, Xinjian,Weng, Jun,Chen, Jinxing,Liu, Yuequn,Gao, Jinpeng,Xu, Chunhe Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

Effects of illumination with xenon or sulfur lamp on growth of tomato seedlings were studied. Results showed no obvious differences in net photosynthetic rate and apparent quantum efficiency. In comparison with xenon lamp, illumination with sulfur lamp slightly reduced ChI a and ChI b content in leaves, relatively shortened epicotyl and hypocotyl length, but significantly increased anthocyanin content of leaves and promoted root growth of tomato seedling plants.

Comparative Study of Effects of Illumination with Xenon or Sulfur Lamp on Development of Wheat Plants

Chen, Qilin,Yu, Xinjian,Chen, Jinxing,Liu, Yuequn,Weng, Jun,Xu, Chunhe Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

The emission of microwave sulfur lamp is mainly composed of visible light. This lamp producing little infrared radiation, has high light efficiency, long lifespan and less power consumption. In comparison with xenon lamp, growing under sulfur lamp apparently postponed jointing, increased the number of tillers, accelerated root growth of wheat. Relatively, xenon lamp evidently promoted heading and grain maturation. The development characteristics of wheat plant under sulfur lamp were more similar with that in natural condition.

Experimental investigation of novel pre-tightened teeth connection technique for composite tube

Fei Li,Qilin Zhao,Haosen Chen,Longxing Xu 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.2

A new composite tube connection method called the pre-tightened teeth connection technique is proposed to improve the composite tube connection efficiency. This paper first introduces the manufacturing process of the proposed technique. It then outlines how the mechanical properties of this technology were tested using four test groups. The factors that influence the load-bearing capacity and damage model of the connection were analyzed, and finally, the transfer load mechanism was investigated. The following conclusions can be obtained from the research results. (1) The new technique improves the compressive connection efficiency by a maximum of 79%, with the efficiency exceeding that of adhesive connections of the same thickness. (2) Changing the depth of teeth results in two types of damage: local compressive damage and shear damage. The bearing capacity can be improved by increasing the depth, length, and number of teeth as well as the pretightening force. (3) The capacity of the technique to transfer high loads is a result of both the relatively high interlaminar shear strength of the pultruded composite and the interlaminar shear strength increase provided by the pre-tightening force. The proposed technique shows favorable mechanical properties, and therefore, it can be extensively applied in the engineering field.

Analytical calculation method for the axial equivalent elastic modulus of laminated FRP pipes based on three-dimensional stress state

Li Chen,Darong Pan,Qilin Zhao,Li-Cheng-Xi Huang,Liang Chen,Wei Xu 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.77 No.1

In engineering design, the axial equivalent elastic modulus of laminated FRP pipe was mostly calculated by the average elastic modulus method or the classical laminated plate theory method, which are based on relatively simplified assumptions, and may be not accurate enough sometimes. A new analytical calculation method for the axial equivalent elastic modulus of laminated FRP pipe was established based on three-dimensional stress state. By comparing the results calculated by this method with those by the above two traditional analytical methods and the finite element method, it is found that this method for the axial equivalent elastic modulus fits well not only for thin-walled pipes with orthotropic layers, but also for thick-walled pipes with arbitrary layers. Besides, the influence of the layer stacking on the axial equivalent elastic modulus was studied with this method. It is found that a proper content of circumferential layer is beneficial for improving the axial equivalent elastic modulus of the laminated FRP pipe with oblique layers, and then can reduce its material quantity under the premise that its axial stiffness remains unchanged. Finally, the meso-mechanical mechanism of this effect was analyzed. The improving effect of circumferential layer on the axial equivalent elastic modulus of the laminated FRP pipe with oblique layers is mainly because that, the circumferential fibers can restrain the rigid body rotations of the oblique fibers, which tend to cause the significant deformations of the pipe wall units and the relatively low axial equivalent elastic modulus of the pipe.

Structural Evaluation of Torsional Rigidity of New FRP–Aluminum Space Truss Bridge with Rigid Transverse Braces

Le Zhu,Dongdong Zhang,Fei Shao,Qian Xu,Qilin Zhao 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.7

A unique fiber-reinforced polymer (FRP)–aluminum spatial truss structure with upper I-type, transverse beam braces was developed for deployable bridging, yielding the operational advantages of bestraddled erection bridges. Experimental testing and numerical simulation were performed to evaluate the torsional rigidity of a fabricated cantilever, full-scale experimental structure. The predictions obtained based on a computational finite element model were strongly consistent with the experimental results. Moreover, a numerical decomposition and reconstruction procedure was employed to understand the load-bearing mechanism of the structure. The results demonstrated that the improved transverse braces possessed adequate capacity for providing sufficient rigidity and lateral stability to the complete twin-treadway structure under torsion. The torsional center of the improved structure was located at the axis of symmetry of the twin-treadway bridge deck. The representative torsional rigidity of the twin-treadway module was approximately 87.5 kN·m2/degree. Compared to the original construction, the improved structure exhibited only minor discrepancies regarding the torsional rigidity, and consistent characteristics in terms of the load-bearing mechanism. The torsional rigidity of the improved twin-treadway structure was primarily generated by the vertical bending rigidities of its two parallel single treadways through the rigid transverse braces. This significant finding specifically pertains to the unique twin-treadway hybrid bridge. The results presented in this work are expected to provide valuable insights, which could, in turn, lead to further the development of similar lightweight structural systems.

Isolation and characterization of a novel piezotolerant bacterium Lysinibacillus yapensis sp. nov., from deep-sea sediment of the Yap Trench, Pacific Ocean

Libo Yu,Xixiang Tang,Shiping Wei,Yinkun Qiu,Xiashutong Xu,Guangxin Xu,Qilin Wang,Qian Yang 한국미생물학회 2019 The journal of microbiology Vol.57 No.7

A Gram-positive, aerobic, rod-shaped, spore-forming bacterium, designated YLB-03T, with peritrichous flagella was isolated from deep-sea sediment of the Yap Trench at a depth of 4435 m. The bacterium was found to be catalase-positive but oxidase-negative. Growth of this bacterium was observed at 15–50°C (optimum 37°C), pH 5–10.5 (optimum 7), 0–5% NaCl (optimum 1%, w/v) and 0.1–50 MPa (optimum 0.1 MPa). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YLB-03T was a member of the genus Lysinibacillus. Strain YLB-03T was closely related to Lysinibacillus sinduriensis BLB-1T and Lysinibacillus chungkukjangi 2RL3-2T (98.4%), Lysinibacillus halotolerans LAM- 612T (98.0%), Lysinibacillus telephonicus KT735049T (97.5%), Lysinibacillus endophyticus C9T (97.5%), Lysinibacillus composti NCCP-36T and Lysinibacillus massiliensis 4400831T (97.3%). The ANI and the GGDC DNA-DNA hybridization estimate values between strain YLB-03T and closely related type strains were 73.7–76.3% and 34.7–38.7%, respectively. The principal fatty acids were anteiso-C15:0 and iso-C15:0. The G+C content of the chromosomal DNA was 39.6 mol%. The respiratory quinone was determined to be MK-7. The diagnostic amino acids in the cell wall peptidoglycan contained Lys-Asp (type A4α) and the cell-wall sugars were glucose and xylose. The polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and an unidentified phospholipid. The combined genotypic and phenotypic data showed that strain YLB-03T represents a novel species within the genus Lysinibacillus, for which the name Lysinibacillus yapensis sp. nov. is proposed, with the type strain YLB-03T (= MCCC 1A12698T = JCM 32871T).