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Optimization of parental RNAi conditions for hunchback gene in Locusta migratoria manilensis （Meyen）

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Insect Science 2010年第1期17卷 1-6页

作者： zheng-Bo He yue-qing Cao Yu-Xian Xia Genetic Engineering Research Center College of Bioengineering Chongqing University Chongqing Engineering Research Center for Fungal Insecticides and Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission Chongqing China

An investigation on the optimization of parental RNA interference （RNAi） conditions for hunchback （hb） gene in Locusta migratoria manilensis （Meyen） was conducted. Double stranded RNA （dsRNA） corresponding to hb gene was injected into haemocoel of female adults ofL. migratoria manilensis. Embryos developed from the eggs laid by the injected adults on the 7th day after eclosion showed observable effects of RNAi for hb. The silencing effect after delivery treatment of dsRNA for hb gene was maintained for more than 21 days. A significant decrease of hb transcripts was further confirmed by Northern blot analysis. The dose of dsRNA/insect at 2μg could trigger 96.9% RNAi effects, while silencing appeared to have no dependence on the size of dsRNA. Results suggest that parental RNAi could be employed to efficiently identify the developmental gene functions in L. migratoria manilensis.

关键词： hunchback Locusta migratoria manilensis parental RNA interference

甲醇对于PEI-SBA固态胺制备及其性能的影响

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化学试剂 2024年第3期46卷 33-38页

作者：胡海涛郑岳青林贻超宁波大学材料科学与化学工程学院浙江宁波315211 中国科学院、宁波材料技术与工程研究所、浙江省先进燃料电池与电解池技术重点实验室浙江宁波315201

固态胺材料具有优异的二氧化碳(CO_(2))选择吸附性能,是一类潜在的CO_(2)捕集材料。作为一种重要的固态胺材料,SBA-15负载聚乙烯亚胺(PEI-SBA-15)由于原材料较为廉价且性能优异受到了大量的关注。PEI-SBA-15的制备过程需要采用甲醇溶剂... 详细信息

固态胺材料具有优异的二氧化碳(CO_(2))选择吸附性能,是一类潜在的CO_(2)捕集材料。作为一种重要的固态胺材料,SBA-15负载聚乙烯亚胺(PEI-SBA-15)由于原材料较为廉价且性能优异受到了大量的关注。PEI-SBA-15的制备过程需要采用甲醇溶剂,而溶剂使用量对于其CO_(2)吸附性能的影响尚无系统研究。系统研究了溶剂使用量对SBA-15负载聚乙烯亚胺的CO_(2)吸附性能的影响。研究结果表明,可以同时实现提升CO_(2)吸附性能和CO_(2)/N_(2)选择性和大幅降低甲醇的使用量。对于降低PEI-SBA-15的制备成本以及提升制备过程环保性具有重要意义。

关键词： SBA-15分子筛 CO_(2)吸附固态胺聚乙烯亚胺溶剂作用碳中和

Synthesis and Characterization of Zinc Succinate, Zn(C4H4O4)

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Chemical Research in Chinese Universities 2001年第1期17卷 20-25页

作者： zheng yue qing ** (Institute for Solid State Chemistry, Ningbo University, Ningbo 315211, P. R. China) 宁波大学浙江宁波 315211 Max-Planck Institute fur Festkor per forschung 德国 D-70569

PETERS Karl and von SCHNERING Hans Georg (Max Planck Institute für Festkrperforschung, D 70569 Stuttgart, Germany)Zn(C 4H 4O 4) prepared by dissolving 0.483 g (1.41 mol) of Zn 3(OH) 4CO 3·H 2O and 0.5 g (4.23 mol) of C 4H 6O 4 in 50 mL of H 2O followed by slow evaporation at room temperature crystallizes in the monoclinic space group C 2 with the cell parameters a =0.757 9(1) nm, b =0.597 6(1) nm , c =0.626 5(1) nm, β =108.45(1)°, V =0.269 17(7) nm 3, D x=2.239 \{g/cm 3\}, Z =2 and the final R(F o)=0.039 and wR(F o 2)=0.088 for 396 reflections [ F o 2≥2 σ(F o 2)]. In the crystal structure unit, each Zn is tetrahedrally coordinated by four O atoms from four (C 4H 4O 4) 2- anions, each of which, in turn, bridges four Zn atoms to build up a 3D \{\} 3 ∞[Zn(C 4H 4O 4) 4/4 ] network. The thermal analyses indicate that Zn(C 4H 4O 4) is stable below 420 ℃.

关键词： Synthesis Zinc succinate Crystal structure Thermal decomposition

Synthesis, Crystal Structure and Magnetic Property of Disodium Biscarbonato cobaltate(Ⅱ) Tetrahydrate, Na_2Co(CO_3)_2·4H_2O

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Chemical Research in Chinese Universities 1999年第4期15卷 311-316页

作者： zheng yue-qing YE Yu-Han HU Fu-Tao PETERS Karl and von SCHNERING Hans Georg Chemistry Department Ningbo UniversityNingbo 315211P.R.China Max Planck Institut für Festkrperforschung D 70569 StuttgartGermany

The title compound, Na 2Co(CO 3) 2·4H 2O, was synthesized by dropwise addition of 1.0 mL of 1 mol/L Co(CH 3COO) 2 to 50 mL of aqueous solution containing 7.0 g(66.0 mmol) of Na 2CO 3 and 2.5 g(29.8 mmol) of NaHCO 3 under stirring. A rose colored rhombohedral crystal grew by the slow evaporation of the solution of the title compoud at room temperature. The crystal structure was established on the basis of the single crystal X ray diffraction data. Na 2Co(CO 3) 2·4H 2O crystallizes in the monoclinic space group C2/c with a =0.856 6(1) nm, b =0.714 6(1) nm, c = 1 438 7(2) nm, β =97.59(1)° , V =0.873 0(2) nm 3 , D x=2.260 g/cm 3, F (000)=596, M r=296 99, μ (Mo K α)=21.06 cm -1 , Z =4 and the final R(F) =0.032 and wR(F 2) =0.068 on the basis of 947 reflections ( F 2 ≥ 2σ(F 0 2)). The crystal consists of H 2O molecules, Na + ions and 2D 2 ∞[Co(CO 3) 2] 2- layers extending parallel to (001). H 2O molecules and Na + cations are located between the 2D layers. Each Co atom is tetrahedrally coordinated by four O atoms from four CO 2- 3 groups with d (Co\_O)=0.206 5(2) nm, 0.207 6(2) nm and the angle of O\_Co\_O is in the range of 97.7(1)°—128.5(1)°. The CO 2- 3 group bridging two Co atoms via two O atoms deviates from D 3h symmetry with d (C\_O)=0.127 2(3)\_0.129 9(3) nm and the angle of O\_C\_O is in the range of 119.5(2)°\_123.4(2)°. Each Na atom, with two close Na neighbours at 0.338 4(2) nm and 0 346 7(2) nm, respectively, is octahedrally coordinated by six O atoms from four H 2O molecules and two carbonate groups belonging to two layers with d (Na\_O)=0.232 7(2)\_0.241 1(2) nm. Of two crystallographically different H 2O molecules, one forms hydrogen bonds to two CO 3 2- groups of one 2D layer, and the other to those from two different 2D layers. Na 2Co(CO 3) 2·4H 2O is antiferromagnetic below 16 K, and between 30\_300

关键词： Synthesis Disodium biscarbonatocobaltate(Ⅱ) tetrahydrate Crystal structure Complex carbonate Magnetic property

A Minimum Residual Based Gradient Iterative Method for a Class of Matrix Equations

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 17-34页

作者： qing-qing zheng Department of Mathematics College of ScienceChina University of Petroleum-BeijingBeijing102249China

In this paper, we present a minimum residual based gradient iterative method for solving a class of matrix equations including Sylvester matrix equations and general coupled matrix equations. The iterative method uses a negative gradient as steepest direction and seeks for an optimal step size to minimize the residual norm of next iterate. It is shown that the iterative sequence converges unconditionally to the exact solution for any initial guess and that the norm of the residual matrix and error matrix decrease monotonically. Numerical tests are presented to show the efficiency of the proposed method and confirm the theoretical results.

关键词： Sylvester matrix equation coupled matrix equation minimum residual gradient descent convergence analysis

Universal method for designing periodic orbits by homotopy classes in the elliptic restricted three-body problem

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Astrodynamics 2024年第1期8卷 175-188页

作者： yue zheng Min Zhao School of Electronic Engineering Xi’an Aeronautical InstituteXi’an710077China School of Aircraft Engineering Xi’an Aeronautical InstituteXi’an710077China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

The current methods for designing periodic orbits in the elliptic restricted three-body problem(ERTBP)have the disadvantages of targeting limited orbits and ergodic searches and considering only symmetric orbits.A universal method for designing periodic orbits is proposed in this ***,the homotopy classes of orbits are structured based on their topological ***,a dynamic model based on homotopy classes,ranging from the circular restricted three-body problem(CRTBP)to the ERTBP,can be built using the homotopy ***,a multi-and a single-period orbit were selected based on the resonance ***,the corresponding orbit in the ERTBP was computed by modifying the initial condition of the orbit in the *** method,without an ergodic search,can extend to any orbit,including an asymmetric orbit in the CRTBP,to the ERTBP model,and the two orbits are of the same homotopy *** of the Earth–Moon ERTBP are presented to verify the efficiency of this method.

关键词： periodic orbit elliptic restricted three-body problem(ERTBP) topology homotopy circular restricted three-body problem(CRTBP)

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： Zhi-Zeng Si yue-yue Wang Chao-qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics

Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： qing-Hui Luo yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

Preface to the "Theory and Applications of Flexoelectricity" Special Issue of Acta Mechanica Solida Sinica

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ACTA MECHANICA SOLIDA SINICA 2024年第4期37卷 519-520页

作者： Deng, Qian zheng, yue Shen, Shengping Huazhong Univ Sci & Technol Sch Aerosp Engn Wuhan 430074 Peoples R China Sun Yat Sen Univ Sch Phys Guangzhou 510275 Peoples R China Xi An Jiao Tong Univ Sch Aerosp Engn Xian 710049 Peoples R China

Flexoelectricity refers to the electric polarization generated by non-uniform mechanical strains within dielectric materials and *** intriguing effect bridges the fields of materials science,mechanical engineering,and applied physics,offering a promising avenue for innovation in sensor technology,energy harvesting,multiphysics field coupling,among others.

关键词： offering bridges harvesting