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Maintenance and Management Model for the Urban Stereo Landscape Forest in Chongqing Academy of Science and Technology 被引量:1
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作者 WANG Zhengchun CHEN Lina +5 位作者 JIANG Haiyan HE Bangliang ZHOU Fei JIANG Xinxing CHEN Daojing YANG Bo 《Journal of Landscape Research》 2012年第11期4-10,共7页
Based on landscaping practices in the stereo landscape demonstration project of Chongqing Academy of Science and Technology (CAST),current management and maintenance of the stereo landscapes were introduced by analyzi... Based on landscaping practices in the stereo landscape demonstration project of Chongqing Academy of Science and Technology (CAST),current management and maintenance of the stereo landscapes were introduced by analyzing maintenance and management of the plants in the stereo landscape forest.The maintenance and management models were summarized according to the management styles,concrete measures and new technologies were studied,laws and key points for the maintenance and management in different seasons were given,and finally deficiencies and solutions were proposed to improve the future maintenance and management. 展开更多
关键词 Management model STEREO LANDSCAPE CHONGQING ACADEMY of Science and Technology (CAST)
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Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes
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作者 Vu D Hop An M Cuong +3 位作者 Phi T T Anh Nguyen T L Huong Le Hoang Nguyen V Hanh 《Asian pacific Journal of Reproduction》 CAS 2024年第5期219-227,共9页
Objective:To determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy outcomes.Methods:This retrospective cohort study was conducted on 291 in... Objective:To determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy outcomes.Methods:This retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June 2023.The EEVA system produced an EEVA score from E1(best)to E5(worse)for the potential of blastocyst formation.Blastocyst morphology was evaluated.The association between the EEVA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating equations.Results:The inner cell mass A(ICM A),trophectoderm A(TE A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the EEVA score.The adjusted odd ratio(aOR)(E5 vs E1)was 0.3 for ICM A,0.174 for TE A and 0.210 for BL3,4,5,6,7(all P<0.001),suggesting a significant association between lower EEVA scores and improved embryo quality.The implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the EEVA score.The aOR of E5 vs E1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(P<0.001).Conclusions:There were associations between blastocyst morphology,pregnancy outcome and EEVA scores.The good blastocyst morphology and pregnancy outcomes are higher with lower the EEVA score. 展开更多
关键词 Automated embryo assessment BLASTOCYST Early embryo viability assessment Genea embryo review incubator MORPHOLOGY Pregnancy outcomes Timelapse
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Possibility of reaching the predicted center of the“island of stability”via the radioactive beam-induced fusion reactions
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作者 Ming-Hao Zhang Ying Zou +3 位作者 Mei-Chen Wang Gen Zhang Qing-Lin Niu Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期186-195,共10页
Based on the dinuclear system model,the synthesis of the predicted double-magic nuclei^(298)Fl and 304120 was investigated via neutron-rich radioactive beam-induced fusion reactions.The reaction^(58)Ca+^(244)Pu is pre... Based on the dinuclear system model,the synthesis of the predicted double-magic nuclei^(298)Fl and 304120 was investigated via neutron-rich radioactive beam-induced fusion reactions.The reaction^(58)Ca+^(244)Pu is predicted to be favorable for producing^(298)Fl with a maximal ER cross section of 0.301 pb.Investigations of the entrance channel effect reveal that the^(244)Pu target is more promising for synthesizing^(298)Fl than the neutron-rich targets^(248)Cm and^(249)Bk,because of the influence of the Coulomb barrier.For the synthesis of 304120,the maximal ER cross section of 0.046 fb emerges in the reaction^(58)V+^(249)Bk,indicating the need for further advancements in both experimental facilities and reaction mechanisms. 展开更多
关键词 Superheavy nuclei Dinuclear system model Fusion reaction Double-magic nucleus Radioactive beam
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Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer
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作者 Heng Zhang Chao Su +2 位作者 Xiaohu Chen Zhizhong Song Weijie Zhan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2977-3000,共24页
Temperature-induced cracking during the construction of mass concrete is a significant concern.Numerical simulations of concrete temperature have primarily assumed that the concrete is placed in an open environment.Th... Temperature-induced cracking during the construction of mass concrete is a significant concern.Numerical simulations of concrete temperature have primarily assumed that the concrete is placed in an open environment.The problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation boundary.However,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it rises.To accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through experiments.Furthermore,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep stress.The results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete temperature.Compared with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 12.5℃ and 0.7 MPa,respectively,under a wind speed of 4 m/s.The results of the traditional calculation method are relatively close to those obtained at a wind speed of 1 m/s.However,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location. 展开更多
关键词 Conjugate heat transfer temperature field mass concrete creep stress
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Investigation and optimization of high-valent Ta-doped SrFeO_(3-δ)as air electrode for intermediate-temperature solid oxide fuel cells
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作者 Shanshan Jiang Hao Qiu +7 位作者 Shaohua Xu Xiaomin Xu Jingjing Jiang Beibei Xiao Paulo Sérgio Barros Juliao) Chao Su Daifen Chen Wei Zhou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2102-2109,共8页
To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_... To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_(3-δ),STF)is investigated and optimized.The effects of Ta^(5+)doping on structure,transition metal reduction,oxygen nonstoichiometry,thermal expansion,and electrical performance are evaluated systematically.Via 10mol%Ta^(5+)doping,the thermal expansion coefficient(TEC)decreased from 34.1×10^(-6)(SrFeO_(3-δ))to 14.6×10^(-6) K^(-1)(STF),which is near the TEC of electrolyte(13.3×10^(-6) K^(-1) for Sm_(0.2)Ce_(0.8)O_(1.9),SDC),indicates excellent thermomechanical compatibility.At 550-750℃,STF shows superior oxygen vacancy concentrations(0.262 to 0.331),which is critical in the oxygen-reduction reaction(ORR).Oxygen temperature-programmed desorption(O_(2)-TPD)indicated the thermal reduction onset temperature of iron ion is around 420℃,which matched well with the inflection points on the thermos-gravimetric analysis and electrical conductivity curves.At 600℃,the STF electrode shows area-specific resistance(ASR)of 0.152Ω·cm^(2) and peak power density(PPD)of 749 mW·cm^(-2).ORR activity of STF was further improved by introducing 30wt%Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)powder,STF+SDC composite cathode achieving outstanding ASR value of 0.115Ω·cm2 at 600℃,even comparable with benchmark cobalt-containing cathode,Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)(BSCF).Distribution of relaxation time(DRT)analysis revealed that the oxygen surface exchange and bulk diffusion were improved by forming a composite cathode.At 650℃,STF+SDC composite cathode achieving an outstanding PPD of 1117 mW·cm^(-2).The excellent results suggest that STF and STF+SDC are promising air electrodes for IT-SOFCs. 展开更多
关键词 strontium ferrite-based perovskite Ta doping composite cathode intermediate-temperature solid oxide fuel cells
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New quantification of symmetry energy from neutron skin thicknesses of^(48)Ca and^(208)Pb
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作者 Rong An Shuai Sun +1 位作者 Li-Gang Cao Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期188-196,共9页
Precise knowledge of the nuclear symmetry energy can be tentatively calibrated using multimessenger constraints.The neutron skin thickness of a heavy nucleus is one of the most sensitive indicators for probing the iso... Precise knowledge of the nuclear symmetry energy can be tentatively calibrated using multimessenger constraints.The neutron skin thickness of a heavy nucleus is one of the most sensitive indicators for probing the isovector components of effective interactions in asymmetric nuclear matter.Recent studies have suggested that the experimental data from the CREX and PREX2 collaborations are not mutually compatible with existing nuclear models.In this study,we review the quantification of the slope parameter of the symmetry energy L from the neutron skin thicknesses of^(48)Ca and^(208)Pb.Skyrme energy density functionals classified by various isoscalar incompressibility coefficients K were employed to evaluate the bulk properties of finite nuclei.The calculated results suggest that the slope parameter L deduced from^(208)Pb is sensitive to the compression modulus of symmetric nuclear matter,but not that from^(48)Ca.The effective parameter sets classified by K=220 MeV can provide an almost overlapping range of L from^(48)Ca and^(208)Pb. 展开更多
关键词 Nuclear symmetry energy Neutron skin thickness Energy density functional
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Prevalence and risk factors associated with long COVID symptoms in children and adolescents in a southern province of Vietnam
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作者 Huynh Ngoc Linh Nguyen The Tan +5 位作者 Le Thi Minh Thu Nguyen Tu Loan Nguyen Thi To Uyen Le Thanh Thao Trang Truong Thanh Nam Doan Hoang Phu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第3期119-128,I0001,I0002,共12页
Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from COVID-19.Methods:This study applied a cross-sectional approach within... Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from COVID-19.Methods:This study applied a cross-sectional approach within community settings in a southern province of Vietnam.A structured questionnaire featuring socio-demographic information and common long COVID symptoms was employed.Phi correlation coefficients assessed associations among pairs of long COVID symptoms.Additionally,multivariable logistic regression models were performed to investigate the risk factors of long COVID in recovered COVID-19 children and adolescents.Results:Among 422 participants,39.3%reported long COVID symptoms,with a prevalence of 45.2%(SD=0.5)in children and 22.2%(SD=0.4)in adolescents.Common symptoms reported were cough 34.6%(SD=0.5),fatigue 20.6%(SD=0.4),shortness of breath 10.9%(SD=0.3),and lack of appetite 6.6%(SD=0.3).Concerning risk factors of long COVID,a higher risk was observed among demographic groups,including girls(OR 1.25,95%CI 1.15-1.37;P<0.001,reference:boys),children compared to adolescents(OR 1.24,95%CI 1.12-1.37;P<0.001),overweight individuals(OR 1.14,95%CI 1.02-1.27;P=0.018,reference:healthy weight),and participants without any COVID-19 vaccination(OR 1.36,95%CI 1.20-1.54;P<0.001),or have received only one single dose(OR 1.35,95%CI 1.10-1.64;P=0.004)compared to those who have received two doses.Besides,patients with a COVID-19 treatment duration exceeding two weeks also had a higher risk of long COVID(OR 1.32,95%CI 1.09-1.60;P=0.003)than those who recovered less than seven days.Conclusions:The insights from this study provide crucial guidance for predicting the factors associated with the occurrence of long COVID in pediatric patients,contributing to strategic interventions aimed at mitigating the long COVID risks among children and adolescents in Vietnam. 展开更多
关键词 Long COVID PREVALENCE Risk factors Children ADOLESCENT VIETNAM
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Taxonomic notes of theridiid spiders (Araneae: Theridiidae) from China and Vietnam
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作者 Ye-Jie Lin Chang-Hao Hu +1 位作者 Dinh-Sac Pham Shu-Qiang Li 《Zoological Research(Diversity and Conservation)》 2024年第2期141-168,共28页
Ten new species of the spider family Theridiidae Sundevall,1833 from China and Vietnam are described:Chrysso shantinggui sp.nov.(♂♀),Gushangzao andaoquan sp.nov.(♂),Moneta oupeng sp.nov.(♂♀),Phycosoma yanshun sp.... Ten new species of the spider family Theridiidae Sundevall,1833 from China and Vietnam are described:Chrysso shantinggui sp.nov.(♂♀),Gushangzao andaoquan sp.nov.(♂),Moneta oupeng sp.nov.(♂♀),Phycosoma yanshun sp.nov.(♂♀),Spinembolia gaofani sp.nov.(♀),S.jiangjing sp.nov.(♂♀),S.lingzhen sp.nov.(♂♀),Stemmops dengfei sp.nov.(♂♀),Takayus xiaorang sp.nov.(♂♀),Yaginumena weidingguo sp.nov.(♀).The unknown sexes of Allothymoites sculptilis Gao&Li,2014,Gyro zeppeli Lin&Li,2024,Parasteatoda longiducta Zhu,1998 are described for the first time. 展开更多
关键词 DIAGNOSIS New combination New species ASIA
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Measurement and prediction of isothermal vapor–liquid equilibrium of a-pinene+camphene/longifolene+abietic acid+palustric acid+neoabietic acid systems 被引量:1
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作者 Youqi Li Xiaopeng Chen +4 位作者 Linlin Wang Xiaojie Wei Weijian Nong Xuejuan Wei Jiezhen Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期155-169,共15页
The vapor–liquid equilibrium(VLE)data of a-pinene+camphene+[abietic acid+palustric acid+neoabietic acid]and a-pinene+longifolene+[abietic acid+palustric acid+neoabietic acid]systems at 313.15 K,333.15 K and 358.15 K ... The vapor–liquid equilibrium(VLE)data of a-pinene+camphene+[abietic acid+palustric acid+neoabietic acid]and a-pinene+longifolene+[abietic acid+palustric acid+neoabietic acid]systems at 313.15 K,333.15 K and 358.15 K were measured by headspace gas chromatography(HSGC).These data was compared with the predictions value by conductor-like screening model for realistic solvation(COSMO-RS).Moreover,the calculated data of COSMO-RS and Non-Random Two-Liquids(NRTL)models showed good agreement with the experimental data.It was found that the three resin acids inhibited the volatility of a-pinene,camphene and longifolene and resulted in the decrease of total pressure.Moreover,HE(HB)contributes the most to the excess enthalpy and the hydrogen bonding interaction is the dominant intermolecular force of a-pinene,camphene and longifolene with the three resin acids.In addition,the geometric structures optimization and binding energy were obtained by the DFT to further illustrate the hydrogen bonding interaction and the effects of the addition of the three resin acids on the isothermal VLE. 展开更多
关键词 Isothermal vapor–liquid equilibrium Headspace gas chromatography COSMO-RS model DFT
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Tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio 被引量:1
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作者 Hung N M Oanh L T M +4 位作者 Chung D P Thang D V Mai V T Hang L T Minh N V 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期561-568,共8页
This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocataly... This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)O.The material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–Teller(BET)surface area,Fourier transform infrared(FTIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(PL).The results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size increase.This change is also observed in the Raman scattering and FTIR spectra with the increase in the vibration frequency of the[PO_(4)]group.The compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding energy.The photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light irradiation.This is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample. 展开更多
关键词 morphology PHOTOCATALYTIC Ag^(+)/PO_(4)^(3-)ratio visible light
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Historical development of karst evergreen broadleaved forests in East Asia has shaped the evolution of a hemiparasitic genus Brandisia(Orobanchaceae)
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作者 Zhe Chen Zhuo Zhou +3 位作者 Ze-Min Guo Truong Van Do Hang Sun Yang Niu 《Plant Diversity》 SCIE CAS CSCD 2023年第5期501-512,共12页
Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern... Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern China.Based on the hemiparasitic and more or less liana habits of this genus,we hypothesized that its evolution and distribution were shaped by the development of EBLFs there.To test our hypothesis,the most comprehensive phylogenies of Brandisia hitherto were constructed based on plastome and nuclear loci(nrDNA,PHYA and PHYB);then divergence time and ancestral areas were inferred using the combined nuclear loci dataset.Phylogenetic analyses reconfirmed that Brandisia is a member of Orobanchaceae,with unstable placements caused by nuclear-plastid incongruences.Within Brandisia,three major clades were well supported,corresponding to the three subgenera based on morphology.Brandisia was inferred to have originated in the early Oligocene(32.69 Mya)in the Eastern Himalayas-SW China,followed by diversification in the early Miocene(19.45 Mya)in karst EBLFs.The differentiation dates of Brandisia were consistent with the origin of keystone species of EBLFs in this region(e.g.,Fagaceae,Lauraceae,Theaceae,and Magnoliaceae)and the colonization of other characteristic groups(e.g.,Gesneriaceae and Mahonia).These findings indicate that the distribution and evolution of Brandisia were facilitated by the rise of the karst EBLFs in East Asia.In addition,the woody and parasitic habits,and pollination characteristics of Brandisia may also be the important factors affecting its speciation and dispersal. 展开更多
关键词 BIOGEOGRAPHY Brandisia Evergreen broadleaved forests(EBLFs) KARST OROBANCHACEAE PHYLOGENY
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Embryonic, genetic and clinical outcomes of fresh versus vitrified oocyte: A retrospective cohort study
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作者 Phuong Dao Thi Son Dang Truong +3 位作者 Thuan Nguyen Duc Anh Pham Van Anh Do Tuan Van Hanh Nguyen 《Asian pacific Journal of Reproduction》 2023年第6期266-272,共7页
Objective:To compare embryonic development,ploidy status and clinical outcomes between fresh and frozen-thawed oocytes.Methods:This retrospective cohort study evaluated 83 fertilization cycles including both fresh and... Objective:To compare embryonic development,ploidy status and clinical outcomes between fresh and frozen-thawed oocytes.Methods:This retrospective cohort study evaluated 83 fertilization cycles including both fresh and frozen oocytes from 79 patients at the HP Fertility Center of Hai Phong International Hospital of Obstetrics and Pediatrics in Vietnam.The patient underwent several ovarian stimulation cycles to accumulate a certain number of oocytes that would be vitrified.In the last oocyte retrieval,all patient’s oocytes including both frozen and fresh would be fertilized.The outcomes included the rates of oocyte survival,cleavage embryo,blastocyst,ploidy status,pregnancy,biochemical pregnancy and clinical pregnancy.Results:The oocyte survival rate after thawing was 96.5%.No statistically significant difference was found when comparing fresh and frozen oocytes regarding fertilization rate(78.1%vs.75.5%,P=0.461),usable cleavage embryo rate(86.9%vs.87.2%,P=0.916)but usable blastocyst rate was found higher statistically in the frozen oocyte group(44.4%vs.54.0%,P=0.049).The percentages of euploid,aneuploid and mosaic embryos between the fresh group and the vitrified group had no significant differences(33.8%vs.31.6%,P=0.682;51.0%vs.54.2%,P=0.569;15.2%vs.12.4%,P=0.787;respectively).The rates of pregnancy,biochemical pregnancy and clinical pregnancy had no statistical difference(68.8%vs.64.8%,P=0.764;12.5%vs.3.6%,P=0.258;37.5%vs.46.4%,P=0.565).17 Mature oocytes are the minimum to have at least one euploid embryo.Conclusions:Oocyte vitrification does not affect embryonic,genetic and clinical results.The number of mature oocytes should be considered for fertilization in some cases. 展开更多
关键词 Clinical outcomes Embryonic development Genetic outcomes Human oocyte Oocyte accumulation Oocyte cryopreservation Ploidy status Vitrified oocyte
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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions 被引量:1
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作者 Ming-Hao Zhang Yu-Hai Zhang +3 位作者 Ying Zou Xiu-Xiu Yang Gen Zhang Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期90-100,共11页
Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental results.The synthesis of superheavy elements Z=121 was systematically studied through co... Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental results.The synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 d.The influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in detail.The reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively. 展开更多
关键词 Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section
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Investigations on the tensile deformation of pure Mg and Mg–15Gd alloy by in-situ X-ray synchrotron radiation and visco-plastic self-consistent modeling
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作者 Yuling Xu Yuanding Huang +5 位作者 Yuye Wang Weiming Gan Shiwei Wang Emad Maawad Norbert Schell Norbert Hort 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第2期607-613,共7页
In this study,the texture evolutions of two Mg materials during tension are explored.In-situ X-ray synchrotron and Visco-Plastic SelfConsistent(VPSC) modeling are employed to investigate the different deformation mode... In this study,the texture evolutions of two Mg materials during tension are explored.In-situ X-ray synchrotron and Visco-Plastic SelfConsistent(VPSC) modeling are employed to investigate the different deformation modes between pure Mg and Mg-15Gd(wt.%) alloy.These two materials with a strong extrusion texture show large different slip/twinning activity behaviors during tensile deformation.The basal(a) slip has the highest contribution to the initial stage of plastic deformation for pure Mg.During the subsequent plastic deformation,the prismatic slip is dominant due to the strong ED//(100) fiber texture.In contrast,the deformation behavior of Mg-15Gd alloy is more complex.Twinning and basal slip are dominant at the early stage of plastic deformation,but further deformation results in the increased activation of prismatic and pyramidal slips.In comparison to pure Mg,the ratios of the critical resolved shear stress(CRSS) between non-basal slip and basal slip of the Mg-15Gd alloy are much lower. 展开更多
关键词 Mg alloy TEXTURE Mechanical behavior In-situ investigation
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Hyphae-mediated bioassembly of carbon fibers derivatives for advanced battery energy storage 被引量:1
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作者 Lei Huang Zhong Qiu +10 位作者 Ping Liu Xinhui Xia Feng Cao Xinping He Chen Wang Wangjun Wan Yongqi Zhang Yang Xia Wenkui Zhang Minghua Chen Jiancang Zhou 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期140-150,共11页
Ingenious design and fabrication of advanced carbon-based sulfur cathodes are extremely important to the development of high-energy lithium-sulfur batteries,which hold promise as the next-generation power source.Herei... Ingenious design and fabrication of advanced carbon-based sulfur cathodes are extremely important to the development of high-energy lithium-sulfur batteries,which hold promise as the next-generation power source.Herein,for the first time,we report a novel versatile hyphae-mediated biological assembly technology to achieve scale production of hyphae carbon fibers(HCFs)derivatives,in which different components including carbon,metal compounds,and semiconductors can be homogeneously assembled with HCFs to form composite networks.The mechanism of biological adsorption assembly is also proposed.As a representative,reduced graphene oxides(rGOs)decorated with hollow carbon spheres(HCSs)successfully co-assemble with HCFs to form HCSs@rGOs/HCFs hosts for sulfur cathodes.In this unique architecture,not only large accommodation space for sulfur but also restrained volume expansion and fast charge transport paths are realized.Meanwhile,multiscale physical barriers plus chemisorption sites are simultaneously established to anchor soluble lithium polysulfides.Accordingly,the designed HCSs@rGOs/HCFs-S cathodes deliver a high capacity(1189 mA h g^(-1)at 0.1 C)and good high-rate capability(686 mA h g^(-1)at 5 C).Our work provides a new approach for the preparation of high-performance carbon-based electrodes for energy storage devices. 展开更多
关键词 bioassembly carbon fibers energy storage graphene lithium-sulfur batteries
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Contributions of Rotation,Expansion and Line Broadening to the Morphology and Kinematics of the Inner CSE of Oxygen-rich AGB Star R Hya
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作者 Pham Tuyet Nhung Do Thi Hoai +4 位作者 Pierre Darriulat Pham Ngoc Diep Nguyen Bich Ngoc Tran Thi Thai Pham Tuan-Anh 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第1期40-47,共8页
We use archival ALMA observations of the CO(2-1)and SiO(5-4)molecular line emissions of AGB star R Hya to illustrate the relative contributions of rotation,expansion and line broadening to the morphology and kinematic... We use archival ALMA observations of the CO(2-1)and SiO(5-4)molecular line emissions of AGB star R Hya to illustrate the relative contributions of rotation,expansion and line broadening to the morphology and kinematics of the circumstellar envelope(CSE)within some~70 au(~0."5)from the centre of the star.We give evidence for rotation and important line broadening to dominate the inner region,within~14 au(~100 mas)from the centre of the star.The former is about an axis that projects a few degrees west of north and has a projected rotation velocity of a few km s^(-1).The latter occurs within some 7-14 au(50-100 mas)from the centre of the star,with the line width reaching two to three times its value outside this region.We suggest that it is caused by shocks induced by stellar pulsations and convective cell granulation.We show the importance of properly accounting for the observed line broadening when discussing rotation and evaluating the radial dependence of the rotation velocity. 展开更多
关键词 STARS AGB and post-AGB-(stars:)circumstellar matter-radio lines
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Study of primordial deuterium abundance in Big Bang nucleosynthesis
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作者 Zhi-Lin Shen Jian-Jun He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期208-215,共8页
Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium... Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d. 展开更多
关键词 Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method
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Truly optimal semi-active damping to control free vibration of a single degree of freedom system
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作者 Viet Duc La Ngoc Tuan Nguyen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期142-145,共4页
This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching ... This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and optimized.The pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping. 展开更多
关键词 Analytical optimization Quadratic integral Lyapunov equation Pontryagin maximum principle
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Investigation of multinucleon transfer processes in the Langevin equation model
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作者 Ying Zou Ming-Hao Zhang +2 位作者 Mei-Chen Wang Yu-Hai Zhang Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期180-187,共8页
Multinucleon transfer in low-energy heavy-ion collisions is increasingly considered a promising approach for generating exotic nuclei.Understanding the complex mechanisms involved in multinucleon transfer processes pr... Multinucleon transfer in low-energy heavy-ion collisions is increasingly considered a promising approach for generating exotic nuclei.Understanding the complex mechanisms involved in multinucleon transfer processes presents significant challenges for the theoretical investigation of nuclear reactions.A Langevin equation model was developed and employed to investigate multinucleon transfer processes.The^(40)Ar+^(232)Th reaction was simulated,and the calculated Wilczyński plot was used to verify the model.Additionally,to study the dynamics of multinucleon transfer reactions,the^(136)Xe+^(238)U and^(136)Xe+^(209)Bi reactions were simulated,and the corresponding TKE-mass and angular distributions were computed to analyze the energy dissipation and scattering angles.This investigation enhances our understanding of the dynamics involved in multinucleon transfer processes. 展开更多
关键词 Reaction mechanisms Multinucleon transfer reactions Langevin equations Wilczyński plot Exotic nuclei
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Environmental Assessment of Coastal Sand Mining Using Proposed DPSIR Criteria:A Case of Hai Phong
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作者 Do Thi Thu Huong Do Gia Khanh +1 位作者 Nguyen Van Thao Tran Dinh Lan 《Sustainable Marine Structures》 2023年第1期14-23,共10页
The environmental impact of coastal sand mining activities in Hai Phong city was assessed using ten proposed sustainable criteria for socio-economic development,and ecological and environmental protection.These ten cr... The environmental impact of coastal sand mining activities in Hai Phong city was assessed using ten proposed sustainable criteria for socio-economic development,and ecological and environmental protection.These ten criteria were developed by the analysis of the Dynamics-Pressure-State-Impact-Response(DPSIR)framework,including one driver and pressure criterion(D and P),seven status and impact criteria(S and I),and two response criteria(R).Each criterion is quantified according to five specific evaluation criteria corresponding to the evaluation score from 1 to 5.The results of the ten criterion application for environmental impact assessment of coastal mining Hai Phong by weighting show that the areas with economic activities,benthic biodiversity,and coastal ecosystems are most negatively impacted(score 4/5 and 3.5/5).Other subjects suffer low to moderate impacts(score 1/5 to 3/5).The environmental impact of sand mining(2015-2020)is generally moderate(score ranging from 2/5 to 3/5).The set of adjusted criteria can be applied to similar activities in coastal provinces and cities in Vietnam. 展开更多
关键词 Coastal area Marine ecosystems Environmental impact VIETNAM
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