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Path analysis of desirable traits and evaluation of reproductive performance of Crassostrea sikamea in different ages

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Aquaculture and Fisheries 2024年第2期9卷 164-171页

作者： Guangqiu chang sheng liu Hongqiang Xu Minhai liu Zhihua Lin Qinggang Xue National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai201306China Ninghai Institute of Mariculture Breeding and Seed Industry Zhejiang Wanli UniversityNinghaiZhejiang Province315604China Key Laboratory of Aquatic Germplasm Resources of Zhejiang Zhejiang Wanli UniversityNingbo315100China

Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell *** to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different *** this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and *** results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell *** weight was the main factor influencing fecundity,and shell height showed a significant correlation with ***,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection *** one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were *** fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto *** results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.

关键词： Crassostrea sikamea Path analysis Reproductive performance Growth traits

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan Nie Hong-chang liu Yue liu Can Wang Jin-lan Xia Wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

Absorption and Fluorescence Emission Spectra of Molecules Containing Azo and/or Oxadiazole Units

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Chemical Research in Chinese Universities 2013年第4期29卷 776-781页

作者： WANG chang-sheng YU Nan liu Peng School of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 P. R. China

The ground state structures of a series of organic molecules containing azo and/or oxadiazole units were obtained by means of density functional theory B3LYP/6-3IG（d） method. The first singlet excited state structures were optimized by virtue of singlet-excitation configuration interaction CIS/6-31G（d） method. The absorption and fluorescence emission spectra were then evaluated via the time-dependent density functional theory B3LYP and PBE1PBE methods with 6-31 l＋＋G（3df,2p） basis set. The calculation results show that compared with those of their parent molecules A-H, B-H, C-H, D-H, the absorption and emission wavelength values of all the derivatives show red shifts. The derivatives containing both the oxadiazole and methoxyl units are good candidates for longer absorption wavelength materials. The effects of azo, oxadiazole, and methoxyl units on the absorption and emission wavelength were discussed.

关键词： Azo Azobenzene Oxadiazole Absorption spectrum Fluorescence emission spectrum Excited state

Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei liu Xiu-quan WANG Jin-long CHEN Guo-ming chang Yuan-jiang sheng Lei-xiang Centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang liu chang-jun Wang chang liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

Characterization of Fe_3Si-based coatings on low silicon steel by pulsed Nd:YAG laser cladding

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 208-214页

作者： Dan-yang Dong chang-sheng liu Sui-yuan Chen Bin Zhang Key Laboratory for Anisotropy and Texture of Materials of the Ministry of Education of China Northeastern University Shenyang 110004 China School of Science College Northeastern University Shenyang 110004 China

The Fe3Si based coating was produced on the Fe-1 Si steel surface by a pulsed Nd：YAG （yttrium aluminum garnet） laser. Its phase constitution and microstructure were characterized by using X-ray diffraction （XRD）, optical microscope （OM）, and field emission scanning electron microscope （FESEM） with associated energy dispersive spectroscopy （EDS） and transmission electron microscopy （TEM）. The hyperfine structure of the coating was studied by Mrssbauer spectra （MS） and the magnetic property was also measured at room temperature by a vibrating sample magnetometer （VSM）. The obtained coating is pore and crack-free with dense microstructure and high Si content. The metallurgical bonding between the coating and the substrate was realized. The microstructure of the coating is typical fine dendrites. The major phase was confirmed by XRD and TEM to be the ordering D03 structured Fe3Si phase. In addition, there were smaller amounts of the Fe5Si3 phase and the γ-Fe phase in the coating. Compared with the substrate, the laser cladding coating has a lower saturation magnetization and a higher coercive force. The poor magnetic property might be because of rapid solidification microstructure and phase constitution in the coating.

关键词： silicon steel laser cladding hyperfine structure magnetic property

Effect of Temperature on Microstructure and Formability of Al-10 mass% Si Coatings

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Journal of Iron and Steel Research International 2016年第3期23卷 270-275页

作者： Jie ZHANG She-ming JIANG Qi-fu ZHANG chang-sheng liu National Engineering Laboratory Advanced Coating Technology for Metals Central Iron and Steel Research InstituteBeijing 100081China School of Materials and Metallurgy Northeastern UniversityShenyang 110004LiaoningChina

The type-1aluminized（Al-10mass% Si）coating on hot stamped steel is used in commercial *** effect of temperature on microstructure and formability of the Al-10mass% Si coating was ***-dip aluminized 22MnB5 steel was heated at 870,900,930,and 1 050 ℃ for 5 *** heat treatment at different temperatures,the microstructure of Al-10mass% Si was characterized by field-emission scanning electron microscopy and energy-dispersive *** results show that when the Al-10mass% Si coating was heated at 870℃for 5min,three types of intermetallic phases were formed：two ternary Fe-Si-Al phases（Fe2SiAl7＋Fe2Si2Al5and Fe2SiAl2＋Fe2Si2Al5）and one binary Fe-Al phase（FeAl3）.The phases in the coating became Fe2SiAl2＋Fe2Si2Al5and FeAl3,the binary Fe-Al phase near the interface became Fe2Al5 and the Si-rich layers were decreased with the increase of heating *** the heat treatment was 1 050℃for 5min,the Si-rich layer disappeared,the coating consisted of FeAl and Fe3 Al,and the Kirkendall voids were *** the heating temperature was increased through 870,900,and 930℃,the coating hardness was reduced and cracks were formed in the coating after hot *** formability of the coating with temperature change was confirmed by a hot stamping *** heated at 1 050 ℃,the coating was formable but continuous Kirkendall voids were observed.

关键词： Al-Si coating heating temperature microstructure formability hot-stamping

Fabrication of wear-resistant layers with lamellar eutectic structure by laser surface alloying using the in situ reaction between Cr and B_4C

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1294-1301页

作者： You-zheng Sun Jin-bao Li Daniel Wellburn chang-sheng liu Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University

To improve the wear resistance of Cr5 steel, wear-resistant layers with lamellar eutectic microstructure were fabricated by laser surface alloying（LSA）, which is dependent on the in situ reaction between Cr and B_4C. Our results indicated that the hypoeutectic structures of the LSA layers were divided into interdendritic eutectic structures and dendrites. The area fraction of the eutectic structures increased with increasing laser scanning speed, which improved the hardness and wear resistance of the LSA layers. The average hardness of the LSA layer prepared at a scanning speed of 8 mm/s was HV_（0.2） 883.9, which was 1.8 times greater than that of the traditional quenched layer（approximately HV 480）. After sliding for 659.4 m, the specimen prepared at a scanning speed of 8 mm/s exhibited a volume loss of 0.0323 mm^3, which was only 29.5% of the volume loss of the traditional quenched specimen.

关键词： eutectic wear resistance laser alloying hardness

Neurotoxicity of tetramethylammonium ion on larval and juvenile zebrafish:Effects on neurobehaviors and multiple biomarkers

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Journal of Environmental Sciences 2024年第9期143卷 138-147页

作者： Ruixin Zhang Rui Wang Jiajun chang GDaniel sheng Daqiang Yin Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Tetramethylammonium hydroxide(TMAH)is an important compound that utilized and released by the rapidly expanding semiconductor industry,which could hardly be removed by the conventional wastewater treatment *** a cholinergic agonist,the tetramethylammonium ion(TMA^(+))has been reported to induce toxicity to muscular and respiratory systems of mammals and human,however the toxicity on aquatic biota remains poorly *** investigated the neurotoxic effects of TMA^(+)exposure on zebrafish,based on neurobehavior tests and a series of *** inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L,and significant alterations on swimming path angles(straight and deflective movements)occurred even at 10 mg/*** tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species(ROS)and malondialdehyde(MDA),significantly negatively related with the activities of antioxidant enzymes,but not significantly correlated with the level of acetylcholinesterase(AChE).Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress,rather than the alterations of *** the highest exposure concentration(200 mg/L),TMA^(+)evoked more severe toxicity on zebrafish juveniles,showing significantly stronger elevation on the MDA activity,and greater inhibitions on the activities of antioxidant enzymes and ACh E,suggesting juveniles were more susceptible to TMA^(+)exposure than larval zebrafish.

关键词： Tetramethylammonium Zebrafish Oxidative stress Acetylcholinesterase Neurobehavior