Recently, a kind of hybrid solution MEA-methanol shows a better CO_2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it...Recently, a kind of hybrid solution MEA-methanol shows a better CO_2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it is necessary to minimize the vaporization of methanol during both the absorption and regeneration processes. In this work, two kinds of hybrid solutions were studied and compared with aqueous MEA solution and MEA-methanol solution, including MEA/TEA/methanol solution and MEA/glycerol/methanol solution. The absorption property of MEA/glycerol/methanol solution is better than aqueous MEA solution within a certain period of time and the absorption property of MEA/TEA/methanol solution is too poor to be used in CO_2 capture. By increasing the concentration of TEA and decreasing the concentration of MEA, the absorption rate, CO_2 capture efficiency and absorption capacity all decreased. Upon adding glycerol, the cyclic capacity decreased and the generation temperature increased, and moreover, the density and viscosity also increased considerably. So after adding TEA and glycerol, the CO_2 capture performance of MEAmethanol solvent cannot be improved.展开更多
A new complex with formula [Cd（3-pbpmb）2 I2]n 1（3-pbpmb = 1,4-bis（pyridine-3-ylmethoxy）benzene）, has been solvothermally synthesized and characterized. The crystal belongs to monoclinic system, space group P21/n...A new complex with formula [Cd（3-pbpmb）2 I2]n 1（3-pbpmb = 1,4-bis（pyridine-3-ylmethoxy）benzene）, has been solvothermally synthesized and characterized. The crystal belongs to monoclinic system, space group P21/n with a = 8.2905（17）, b = 16.078（3）, c = 13.213（3）A, β = 99.44（3）°, Mr = 950.86, V = 1737.3（6） A^3, Z = 2, Dc = 1.818 g/cm^3, F（000） = 924, m = 2.450 mm（-1）, the final R = 0.0198 and w R = 0.0467 for 3053 observed reflections（I ＆gt; 2σ（I））. The Cd（Ⅱ） ion is coordinated by four N atoms of four 3-pbpmb ligands and two iodine ions to furnish a distorted octahedral coordination geometry. The Cd（Ⅱ） ion and its own symmetry-related ions are bridged by N atoms from two 3-pbpmb ligands to generate a ＂zigzag＂ 1-D chain coordination polymer. These 1D chains are further connected into a three-dimensional（3D） framework by C–H×××pinteractions and intermolecular C–H×××I hydrogen bond. Interestingly, 1 displays efficient sorption of molecular iodine gas（up to 111 wt%）, but invalid sorption of molecular water gas.展开更多
The preparation of hydrogel adsorbents with admirable performance for efficient selective remove Pb(Ⅱ)in complex wastewater still remains a great challenge.Herein,a novel bifunctional modified polymer hydrogel PAM-PA...The preparation of hydrogel adsorbents with admirable performance for efficient selective remove Pb(Ⅱ)in complex wastewater still remains a great challenge.Herein,a novel bifunctional modified polymer hydrogel PAM-PAMPS was prepared by crosslinking acrylamide(AM)and 2-acrylamido-2-methylpropanesulfonic acid(AMPS).Compared with PEG,PAA and PAMPS,PAM-PAMPS exhibited both the maximum adsorption capacity of Pb(Ⅱ)(541.90 mg/g)and satisfactory selectivity for Pb(Ⅱ)in multiple heavy metal ions coexistence solutions.Various characterizations indicated that–SO3H and–NH2as active sites on PAM-PAMPS occur the synergistic effects of ion-exchange and coordination with Pb(Ⅱ)during the adsorption process,respectively.The adsorption energy Ead(PAM-PAMPS)obtained from density functional theory(DFT)calculations was lower than the other three hydrogels,manifesting that PAMPAMPS formed the most stable complex with Pb(Ⅱ),which further demonstrated that Pb(Ⅱ)preferred to combine with PAM-PAMPS to selective capture of Pb(Ⅱ).The practice utilization of PAM-PAMPS was assessed by wastewater of electroplate containing Pb(Ⅱ).Meanwhile,the removal ratio of PAM-PAMPS was maintained at about 89%after 4 adsorption-desorption cycles.This study establishes a new and effective idea for the design and fabrication of bifunctionalized modified polymer hydrogels.展开更多
The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed d...The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed during differentiation and development. In the present study, over 10,000 primary spermatocytes and round spermatid cells weresuccessfully isolated by LCM. Using the cDNAs from primary spermatocytes and round spermatids, SSH cDNAs library of primary spermatocyte-specific was constructed. The average insert size of the cDNA isolated from 75 randomly picked white clones was 500 bp, ranging from 250 bp to 1.7 kb. Using the dot-blot method, a total of 421 clones were examined, resulting in the identification of 390 positive clones emitting strong signals. Partial sequence of cDNAs prepared from each clone was determined with an overall success rate of 84.4%. Genes encoding cytochrome c oxidase Ⅱ and the rescue factor-humanin were most frequently expressed in primary spermatocytes, suggesting their roles involved in meiosis.展开更多
A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3-(trimethoxysilyl)propyl] ethylene diamine(TMSPEDA) with epichlorohydrin(ECH) via a sol–gel process.Fourier transform...A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3-(trimethoxysilyl)propyl] ethylene diamine(TMSPEDA) with epichlorohydrin(ECH) via a sol–gel process.Fourier transform infrared(FTIR) spectra confirmed that the reaction occurred.TGA curves showed that the thermal stability of these hybrid adsorbents reached as high as 180 °C.As a typical example,the adsorption performance of nickel(II) ions onto an adsorbent(the volume ratio of TMSPEDA and ECH was 4:1) was explored.It was found that the adsorption of nickel(II) ions onto this adsorbent followed the Lagergren pseudo-second-order kinetic model.The investigation of the adsorption mechanism demonstrated that nickel(II) adsorption was chiefly controlled by diffusion–chemisorption,suggesting that more diffusion processes were involved in the adsorption of nickel(II) ions onto this type of adsorbents.Desorption experiment indicates that these hybrid adsorbents can be regenerated.These findings reveal that this type of silica-based hybrid adsorbent is promising in the separation and recovery of nickel(II) ions from Ni-containing wastewater or contaminated water.展开更多
Motivated by inconveniences of present hybrid methods,a gradient-augmented hybrid interface capturing method（GAHM） is presented for incompressible two-phase flow.A front tracking method（FTM） is used as the skeleto...Motivated by inconveniences of present hybrid methods,a gradient-augmented hybrid interface capturing method（GAHM） is presented for incompressible two-phase flow.A front tracking method（FTM） is used as the skeleton of the GAHM for low mass loss and resources.Smooth eulerian level set values are calculated from the FTM interface,and are used for a local interface reconstruction.The reconstruction avoids marker particle redistribution and enables an automatic treatment of interfacial topology change.The cubic Hermit interpolation is employed in all steps of the GAHM to capture subgrid structures within a single spacial cell.The performance of the GAHM is carefully evaluated in a benchmark test.Results show significant improvements of mass loss,clear subgrid structures,highly accurate derivatives（normals and curvatures） and low cost.The GAHM is further coupled with an incompressible multiphase flow solver,Super CE/SE,for more complex and practical applications.The updated solver is evaluated through comparison with an early droplet research.展开更多
We study the Kondo screening of a spin-1/2 magnetic impurity in the hybrid nodal line semimetals(NLSMs) and the type-Ⅱ NLSMs by using the variational method. We mainly study the binding energy and the spin–spin corr...We study the Kondo screening of a spin-1/2 magnetic impurity in the hybrid nodal line semimetals(NLSMs) and the type-Ⅱ NLSMs by using the variational method. We mainly study the binding energy and the spin–spin correlation between magnetic impurity and conduction electrons. We find that in both the hybrid and type-Ⅱ cases, the density of states(DOS) is always finite, so the impurity and the conduction electrons always form bound states, and the bound state is more easily formed when the DOS is large. Meanwhile, due to the unique dispersion relation and the spin–orbit couplings in the NLSMs, the spatial spin–spin correlation components show very interesting features. Most saliently, various components of the spatial spin–spin correlation function decay with 1/r^(2) in the hybrid NLSMs, while they follow 1/r^(3) decay in the type-Ⅱ NLSMs. This property is mainly caused by the special band structures in the NLSMs, and it can work as a fingerprint to distinguish the two types of NLSMs.展开更多
风电、光伏等可再生能源在微电网的渗透率日益增加,使得交直流混合微电网经济调度难度加大。为实现含高渗透率可再生能源的交直流混合微电网的优化运行,结合分时电价机制,对蓄电池充放电策略进行研究。以经济成本和总节点电压偏差为优...风电、光伏等可再生能源在微电网的渗透率日益增加,使得交直流混合微电网经济调度难度加大。为实现含高渗透率可再生能源的交直流混合微电网的优化运行,结合分时电价机制,对蓄电池充放电策略进行研究。以经济成本和总节点电压偏差为优化的目标函数,建立考虑蓄电池荷电状态和公共直流母线关键节点电压偏差的多目标优化模型;针对非支配排序遗传算法(non-dominated sorting in genetic algorithm-Ⅱ,NSGA-Ⅱ)只能求出一个非劣解集的特点,将NSGA-Ⅱ和模糊决策相结合,利用模糊决策从非劣解集中寻找最优解。最后针对交直流混合微电网算例,求出交直流混合微电网的优化调度策略,结果表明该算法能有效降低交直流混合微电网运行成本以及公共直流母线关键节点的电压偏差。展开更多
风电并网在实现节约化石能源和减少有害气体排放等效益的同时,也将对电力系统的可靠性造成一定的负面影响。为达到投资经济性、系统可靠性、环保效果的整体最优,构建了多目标风电场接入的输电线路与电网的联合优化规划模型;针对目标权...风电并网在实现节约化石能源和减少有害气体排放等效益的同时,也将对电力系统的可靠性造成一定的负面影响。为达到投资经济性、系统可靠性、环保效果的整体最优,构建了多目标风电场接入的输电线路与电网的联合优化规划模型;针对目标权重未知、人工神经网络(artificial neuralnetwork,ANN)收敛困难、无法合理决策等问题,采用方差最大化决策和分类逼近理想解的排序方法(technique fororder preference by similarity to an ideal solution,TOPSIS)缩小最优解的范围,并在此基础上提出了随机模拟、神经元网络和非劣排序遗传算法II(non-dominated sorting geneticalgorithm II,NSGA-Ⅱ)相结合的混合智能算法;对增加风电场的改进IEEE Garver-6系统进行计算分析,结果表明该方法具有较高的决策效率和计算精度,从而验证了所提出模型和方法的合理性和有效性。展开更多
基金supported by the Sinopec Ningbo Engineering Co., Ltd. (No. 14850000-14-ZC0609-0003, H8XY-0032)
文摘Recently, a kind of hybrid solution MEA-methanol shows a better CO_2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it is necessary to minimize the vaporization of methanol during both the absorption and regeneration processes. In this work, two kinds of hybrid solutions were studied and compared with aqueous MEA solution and MEA-methanol solution, including MEA/TEA/methanol solution and MEA/glycerol/methanol solution. The absorption property of MEA/glycerol/methanol solution is better than aqueous MEA solution within a certain period of time and the absorption property of MEA/TEA/methanol solution is too poor to be used in CO_2 capture. By increasing the concentration of TEA and decreasing the concentration of MEA, the absorption rate, CO_2 capture efficiency and absorption capacity all decreased. Upon adding glycerol, the cyclic capacity decreased and the generation temperature increased, and moreover, the density and viscosity also increased considerably. So after adding TEA and glycerol, the CO_2 capture performance of MEAmethanol solvent cannot be improved.
基金supported by the National Natural Science Foundation of China(No.21071006)Henan Province Key Laboratory of New Optoelectronic Functional Materials(No.aynu201703)Anyang Normal University Breeding Fund
文摘A new complex with formula [Cd（3-pbpmb）2 I2]n 1（3-pbpmb = 1,4-bis（pyridine-3-ylmethoxy）benzene）, has been solvothermally synthesized and characterized. The crystal belongs to monoclinic system, space group P21/n with a = 8.2905（17）, b = 16.078（3）, c = 13.213（3）A, β = 99.44（3）°, Mr = 950.86, V = 1737.3（6） A^3, Z = 2, Dc = 1.818 g/cm^3, F（000） = 924, m = 2.450 mm（-1）, the final R = 0.0198 and w R = 0.0467 for 3053 observed reflections（I ＆gt; 2σ（I））. The Cd（Ⅱ） ion is coordinated by four N atoms of four 3-pbpmb ligands and two iodine ions to furnish a distorted octahedral coordination geometry. The Cd（Ⅱ） ion and its own symmetry-related ions are bridged by N atoms from two 3-pbpmb ligands to generate a ＂zigzag＂ 1-D chain coordination polymer. These 1D chains are further connected into a three-dimensional（3D） framework by C–H×××pinteractions and intermolecular C–H×××I hydrogen bond. Interestingly, 1 displays efficient sorption of molecular iodine gas（up to 111 wt%）, but invalid sorption of molecular water gas.
基金financially supported by the National Science Fund for Distinguished Young Scholars(No.52125002)the National Science Foundation of China(No.52100043)+1 种基金the National Key Research and Development Program of China(No.2019YFC1907900)the National Science Foundation of Jiangxi Province(No.20224BAB203048)。
文摘The preparation of hydrogel adsorbents with admirable performance for efficient selective remove Pb(Ⅱ)in complex wastewater still remains a great challenge.Herein,a novel bifunctional modified polymer hydrogel PAM-PAMPS was prepared by crosslinking acrylamide(AM)and 2-acrylamido-2-methylpropanesulfonic acid(AMPS).Compared with PEG,PAA and PAMPS,PAM-PAMPS exhibited both the maximum adsorption capacity of Pb(Ⅱ)(541.90 mg/g)and satisfactory selectivity for Pb(Ⅱ)in multiple heavy metal ions coexistence solutions.Various characterizations indicated that–SO3H and–NH2as active sites on PAM-PAMPS occur the synergistic effects of ion-exchange and coordination with Pb(Ⅱ)during the adsorption process,respectively.The adsorption energy Ead(PAM-PAMPS)obtained from density functional theory(DFT)calculations was lower than the other three hydrogels,manifesting that PAMPAMPS formed the most stable complex with Pb(Ⅱ),which further demonstrated that Pb(Ⅱ)preferred to combine with PAM-PAMPS to selective capture of Pb(Ⅱ).The practice utilization of PAM-PAMPS was assessed by wastewater of electroplate containing Pb(Ⅱ).Meanwhile,the removal ratio of PAM-PAMPS was maintained at about 89%after 4 adsorption-desorption cycles.This study establishes a new and effective idea for the design and fabrication of bifunctionalized modified polymer hydrogels.
文摘The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed during differentiation and development. In the present study, over 10,000 primary spermatocytes and round spermatid cells weresuccessfully isolated by LCM. Using the cDNAs from primary spermatocytes and round spermatids, SSH cDNAs library of primary spermatocyte-specific was constructed. The average insert size of the cDNA isolated from 75 randomly picked white clones was 500 bp, ranging from 250 bp to 1.7 kb. Using the dot-blot method, a total of 421 clones were examined, resulting in the identification of 390 positive clones emitting strong signals. Partial sequence of cDNAs prepared from each clone was determined with an overall success rate of 84.4%. Genes encoding cytochrome c oxidase Ⅱ and the rescue factor-humanin were most frequently expressed in primary spermatocytes, suggesting their roles involved in meiosis.
基金Supported by the National Natural Science Foundation of China(21376059)the Key Discipline of Hefei University(2014xk01)
文摘A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3-(trimethoxysilyl)propyl] ethylene diamine(TMSPEDA) with epichlorohydrin(ECH) via a sol–gel process.Fourier transform infrared(FTIR) spectra confirmed that the reaction occurred.TGA curves showed that the thermal stability of these hybrid adsorbents reached as high as 180 °C.As a typical example,the adsorption performance of nickel(II) ions onto an adsorbent(the volume ratio of TMSPEDA and ECH was 4:1) was explored.It was found that the adsorption of nickel(II) ions onto this adsorbent followed the Lagergren pseudo-second-order kinetic model.The investigation of the adsorption mechanism demonstrated that nickel(II) adsorption was chiefly controlled by diffusion–chemisorption,suggesting that more diffusion processes were involved in the adsorption of nickel(II) ions onto this type of adsorbents.Desorption experiment indicates that these hybrid adsorbents can be regenerated.These findings reveal that this type of silica-based hybrid adsorbent is promising in the separation and recovery of nickel(II) ions from Ni-containing wastewater or contaminated water.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10972010,11028206,11371069,11372052,11402029,and 11472060)the Science and Technology Development Foundation of China Academy of Engineering Physics(CAEP),China(Grant No.2014B0201030)the Defense Industrial Technology Development Program of China(Grant No.B1520132012)
文摘Motivated by inconveniences of present hybrid methods,a gradient-augmented hybrid interface capturing method（GAHM） is presented for incompressible two-phase flow.A front tracking method（FTM） is used as the skeleton of the GAHM for low mass loss and resources.Smooth eulerian level set values are calculated from the FTM interface,and are used for a local interface reconstruction.The reconstruction avoids marker particle redistribution and enables an automatic treatment of interfacial topology change.The cubic Hermit interpolation is employed in all steps of the GAHM to capture subgrid structures within a single spacial cell.The performance of the GAHM is carefully evaluated in a benchmark test.Results show significant improvements of mass loss,clear subgrid structures,highly accurate derivatives（normals and curvatures） and low cost.The GAHM is further coupled with an incompressible multiphase flow solver,Super CE/SE,for more complex and practical applications.The updated solver is evaluated through comparison with an early droplet research.
基金supported by the Zhejiang Provincial Natural Science Foundation of China (Grant No. LY19A040003)。
文摘We study the Kondo screening of a spin-1/2 magnetic impurity in the hybrid nodal line semimetals(NLSMs) and the type-Ⅱ NLSMs by using the variational method. We mainly study the binding energy and the spin–spin correlation between magnetic impurity and conduction electrons. We find that in both the hybrid and type-Ⅱ cases, the density of states(DOS) is always finite, so the impurity and the conduction electrons always form bound states, and the bound state is more easily formed when the DOS is large. Meanwhile, due to the unique dispersion relation and the spin–orbit couplings in the NLSMs, the spatial spin–spin correlation components show very interesting features. Most saliently, various components of the spatial spin–spin correlation function decay with 1/r^(2) in the hybrid NLSMs, while they follow 1/r^(3) decay in the type-Ⅱ NLSMs. This property is mainly caused by the special band structures in the NLSMs, and it can work as a fingerprint to distinguish the two types of NLSMs.
文摘风电、光伏等可再生能源在微电网的渗透率日益增加,使得交直流混合微电网经济调度难度加大。为实现含高渗透率可再生能源的交直流混合微电网的优化运行,结合分时电价机制,对蓄电池充放电策略进行研究。以经济成本和总节点电压偏差为优化的目标函数,建立考虑蓄电池荷电状态和公共直流母线关键节点电压偏差的多目标优化模型;针对非支配排序遗传算法(non-dominated sorting in genetic algorithm-Ⅱ,NSGA-Ⅱ)只能求出一个非劣解集的特点,将NSGA-Ⅱ和模糊决策相结合,利用模糊决策从非劣解集中寻找最优解。最后针对交直流混合微电网算例,求出交直流混合微电网的优化调度策略,结果表明该算法能有效降低交直流混合微电网运行成本以及公共直流母线关键节点的电压偏差。
文摘风电并网在实现节约化石能源和减少有害气体排放等效益的同时,也将对电力系统的可靠性造成一定的负面影响。为达到投资经济性、系统可靠性、环保效果的整体最优,构建了多目标风电场接入的输电线路与电网的联合优化规划模型;针对目标权重未知、人工神经网络(artificial neuralnetwork,ANN)收敛困难、无法合理决策等问题,采用方差最大化决策和分类逼近理想解的排序方法(technique fororder preference by similarity to an ideal solution,TOPSIS)缩小最优解的范围,并在此基础上提出了随机模拟、神经元网络和非劣排序遗传算法II(non-dominated sorting geneticalgorithm II,NSGA-Ⅱ)相结合的混合智能算法;对增加风电场的改进IEEE Garver-6系统进行计算分析,结果表明该方法具有较高的决策效率和计算精度,从而验证了所提出模型和方法的合理性和有效性。
