Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_4VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the ...Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_4VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_4VO_(3)by adding(NH_4)_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_4VO_(3)and NaHCO_(3),respectively.展开更多
目的探究胚胎发育过程中的形态动力学参数对整倍体单囊胚移植后妊娠结局的影响。方法回顾性队列研究分析2019年1月至2021年6月期间于重庆医科大学附属妇女儿童医院生殖医学中心接受胚胎植入前遗传学检测-整倍体囊胚解冻复苏移植治疗的39...目的探究胚胎发育过程中的形态动力学参数对整倍体单囊胚移植后妊娠结局的影响。方法回顾性队列研究分析2019年1月至2021年6月期间于重庆医科大学附属妇女儿童医院生殖医学中心接受胚胎植入前遗传学检测-整倍体囊胚解冻复苏移植治疗的394例患者临床资料。根据妊娠结局分为未着床组(n=153)、临床流产组(n=16)和活产组(n=225)。比较各组患者的一般资料、胚胎质量及形态动力学参数的差异。结果未着床组女性的年龄[(32.51±4.08)岁]大于活产组患者[(31.34±4.23)岁,P=0.025],优质胚胎率[26.80%(41/153)]低于活产组[42.22%(95/225),P=0.007]。与临床流产组相比,未着床组的体质量指数、优质胚胎率差异均无统计学意义(均P>0.05)。三组间的形态动力学参数原核出现时间(time to pronuclei appearance,tPNa)、原核消失时间(time to PN fading,tPNf)、2-细胞时间(time to 2-cell,t2)、t3、t4及t8差异均无统计学意义(均P>0.05)。未着床组胚胎的桑椹胚融合时间(timing of compacted morula,tM)[(86.96±7.59)h]、开始形成囊胚腔的时间[(96.73±7.20)h)]均显著高于活产组[(85.00±7.00)h,P=0.010;(95.14±7.30)h,P=0.037]和临床流产组[(82.89±6.33)h,P=0.040;(93.02±6.10)h,P=0.048]。校正年龄和胚胎质量因素后,二元logistic回归结果显示形态动力学参数对着床和活产结局差异均无统计学意义(均P>0.05)。结论胚胎发育过程中的形态动力学参数不影响整倍体单囊胚移植的妊娠结局,不能用于预测整倍体囊胚移植的妊娠结局。展开更多
为探明不同氮钾配比和玉米茎秆抗倒伏性能及产量特性的内在联系,在松嫩平原西部采用田间裂区设计(主区为施氮量,副区为施钾量),研究了不同氮钾水平(N:195、210、225、240 kg·hm-2;K2O:70、85、100、115 kg·hm-2)配比对灌浆期...为探明不同氮钾配比和玉米茎秆抗倒伏性能及产量特性的内在联系,在松嫩平原西部采用田间裂区设计(主区为施氮量,副区为施钾量),研究了不同氮钾水平(N:195、210、225、240 kg·hm-2;K2O:70、85、100、115 kg·hm-2)配比对灌浆期玉米茎秆形态力学特征及籽粒产量的影响。结果表明:氮肥单因素对株高、钾肥单因素对重心高度的影响明显,而氮钾肥互作对于株高、穗位高和重心高度均未达显著水平;氮、钾肥单因素及其互作对节间长度、茎粗、截面面积、节间充实度、抗折力、穿刺强度、断面模数、秆型指数、弯曲力矩、抗断弯距、弯曲应力均表现出显著(P<0.05)或极显著(P<0.01)的影响,在不同组合处理中,以210 kg N·hm-2+85 kg K2O·hm-2处理的抗倒伏指数最大,其次为225 kg N·hm-2+100kg K2O·hm-2和210 kg N·hm-2+100 kg K2O·hm-2处理,显著高于其他处理组合31.59%~80.86%,同时氮、钾肥对玉米抗倒伏指数的互作效应显著(FN×K=19.577**);综合玉米茎秆形态力学特性与产量水平,松嫩平原西部玉米丰产抗倒伏的氮钾肥优化配施方案为:施210~225 kg N·hm-2+85~100 kg K2O·hm-2,氮钾配比为1.75~1.88∶0.71~0.83。本研究结果可为松嫩平原玉米密植丰产提质增抗的养分高效运筹模式提供科学依据和技术途径。展开更多
The hot deformation behavior of 7A55 aluminum alloy was investigated at the temperature ranging from 300 ℃ to 450 ℃ and strain rate ranging from 0.01 s-1 to 1 s-1 on a Gleeble-3500 simulator. Processing maps were es...The hot deformation behavior of 7A55 aluminum alloy was investigated at the temperature ranging from 300 ℃ to 450 ℃ and strain rate ranging from 0.01 s-1 to 1 s-1 on a Gleeble-3500 simulator. Processing maps were established in order to apprehend the kinetics of hot deformation and the rate controlling mechanism was interpreted by the kinetic rate analysis obeying power-law relation. The results indicated that one significant domain representing dynamic recrystallization （DRX） existed on the processing maps and lying in 410-450 ＆#176;C and 0.05-1 s-1. The conclusions of kinetic analysis correlated well with those obtained from processing maps. The apparent activation energy values calculated in the dynamic recrystallization （DRX） domain and the stability regions except dynamic recrystallization （DRX） domain were 91.2 kJ/mol and 128.8 kJ/mol, respectively, which suggested that grain boundary self-diffusion and cross-slip were the rate controlling mechanisms.展开更多
基金the financial supports from the National Natural Science Foundation of China(No.22078343)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0430103)the National Key Research and Development Program of China(No.2018YFC1900502)。
文摘Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_4VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_4VO_(3)by adding(NH_4)_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_4VO_(3)and NaHCO_(3),respectively.
文摘目的探究胚胎发育过程中的形态动力学参数对整倍体单囊胚移植后妊娠结局的影响。方法回顾性队列研究分析2019年1月至2021年6月期间于重庆医科大学附属妇女儿童医院生殖医学中心接受胚胎植入前遗传学检测-整倍体囊胚解冻复苏移植治疗的394例患者临床资料。根据妊娠结局分为未着床组(n=153)、临床流产组(n=16)和活产组(n=225)。比较各组患者的一般资料、胚胎质量及形态动力学参数的差异。结果未着床组女性的年龄[(32.51±4.08)岁]大于活产组患者[(31.34±4.23)岁,P=0.025],优质胚胎率[26.80%(41/153)]低于活产组[42.22%(95/225),P=0.007]。与临床流产组相比,未着床组的体质量指数、优质胚胎率差异均无统计学意义(均P>0.05)。三组间的形态动力学参数原核出现时间(time to pronuclei appearance,tPNa)、原核消失时间(time to PN fading,tPNf)、2-细胞时间(time to 2-cell,t2)、t3、t4及t8差异均无统计学意义(均P>0.05)。未着床组胚胎的桑椹胚融合时间(timing of compacted morula,tM)[(86.96±7.59)h]、开始形成囊胚腔的时间[(96.73±7.20)h)]均显著高于活产组[(85.00±7.00)h,P=0.010;(95.14±7.30)h,P=0.037]和临床流产组[(82.89±6.33)h,P=0.040;(93.02±6.10)h,P=0.048]。校正年龄和胚胎质量因素后,二元logistic回归结果显示形态动力学参数对着床和活产结局差异均无统计学意义(均P>0.05)。结论胚胎发育过程中的形态动力学参数不影响整倍体单囊胚移植的妊娠结局,不能用于预测整倍体囊胚移植的妊娠结局。
文摘为探明不同氮钾配比和玉米茎秆抗倒伏性能及产量特性的内在联系,在松嫩平原西部采用田间裂区设计(主区为施氮量,副区为施钾量),研究了不同氮钾水平(N:195、210、225、240 kg·hm-2;K2O:70、85、100、115 kg·hm-2)配比对灌浆期玉米茎秆形态力学特征及籽粒产量的影响。结果表明:氮肥单因素对株高、钾肥单因素对重心高度的影响明显,而氮钾肥互作对于株高、穗位高和重心高度均未达显著水平;氮、钾肥单因素及其互作对节间长度、茎粗、截面面积、节间充实度、抗折力、穿刺强度、断面模数、秆型指数、弯曲力矩、抗断弯距、弯曲应力均表现出显著(P<0.05)或极显著(P<0.01)的影响,在不同组合处理中,以210 kg N·hm-2+85 kg K2O·hm-2处理的抗倒伏指数最大,其次为225 kg N·hm-2+100kg K2O·hm-2和210 kg N·hm-2+100 kg K2O·hm-2处理,显著高于其他处理组合31.59%~80.86%,同时氮、钾肥对玉米抗倒伏指数的互作效应显著(FN×K=19.577**);综合玉米茎秆形态力学特性与产量水平,松嫩平原西部玉米丰产抗倒伏的氮钾肥优化配施方案为:施210~225 kg N·hm-2+85~100 kg K2O·hm-2,氮钾配比为1.75~1.88∶0.71~0.83。本研究结果可为松嫩平原玉米密植丰产提质增抗的养分高效运筹模式提供科学依据和技术途径。
基金Project(2012CB619505)supported by the National Basic Research Program of China
文摘The hot deformation behavior of 7A55 aluminum alloy was investigated at the temperature ranging from 300 ℃ to 450 ℃ and strain rate ranging from 0.01 s-1 to 1 s-1 on a Gleeble-3500 simulator. Processing maps were established in order to apprehend the kinetics of hot deformation and the rate controlling mechanism was interpreted by the kinetic rate analysis obeying power-law relation. The results indicated that one significant domain representing dynamic recrystallization （DRX） existed on the processing maps and lying in 410-450 ＆#176;C and 0.05-1 s-1. The conclusions of kinetic analysis correlated well with those obtained from processing maps. The apparent activation energy values calculated in the dynamic recrystallization （DRX） domain and the stability regions except dynamic recrystallization （DRX） domain were 91.2 kJ/mol and 128.8 kJ/mol, respectively, which suggested that grain boundary self-diffusion and cross-slip were the rate controlling mechanisms.
