Identification of transgene insertions in two genetically modified soybeans using high throughput next generation sequencing

Genetically modified(GM) organisms are widely adopted. However, their safety assessments and control are still of special concern to the public. Identifying and localizing transgene insertion is an essentially prerequisite step. In this study, 2 independent transgene soybean lines were selected(LB4-AtDCGS-1-20-5-2 and CGS-ZG11) as typical cases. Both lines contained expression cassette of At-DCGS that encoding a feedback-insensitive cystathionine gamma-synthase to produce higher level methionine(Met). LB4-AtDCGS-1-20-5-2 was whole genome sequenced with one paired-end 500 bp library and two mate-paired 1 kb and 2 kb libraries using Illumina HiSeq sequencing platform. CGS-ZG11 was sequenced with only one paired-end 500 bp library. Both genomes were assembled,and 2 scaffold sequences(1 for each line) were screened out by aligning with transgene.Then the transgene insertion and its flanking regions in soybean genome were further identified and confirmed by PCR cloning and Sanger sequencing. Results showed that these 2 transgene lines had single copy of inserted transgene. Their transgene insertion contents were identified, which facilitates further safety assessment. These results indicated that genome assembly using high throughput sequencing is a powerful tool for identifying transgene insertions, even with limited knowledge.

金属有机框架衍生的氮掺杂碳包覆空心管In_(2)O_(3)/CdZnS异质结用于高效光催化析氢

光催化析氢(PHE)技术是解决当前能源短缺问题的有力途径之一.本文采用简单的油浴加热方法原位合成了六方空心管状氮掺杂碳包覆的In_(2)O_(3)/CdZnS异质结光催化剂.结果表明,N-C/In_(2)O_(3)/CdZnS(~22.87μmol h-1)的光催化析氢速率是原始CdZnS(~9.49μmol h-1)的~2.4倍,是原始In_(2)O_(3)(~0.42μmol h-1)的~54.5倍.经过4个循环后,光催化析氢量仍能达到原来的90%以上.其优异的光催化性能主要归功于以下几个方面:(1)氮掺杂碳层作为电子传输桥梁,保证了光催化反应的高效电子转移;(2)中空管状结构增强了光的反射,增强了光吸收性能;(3)形成N-C/In_(2)O_(3)/CdZnS异质结构,改善了载流子复合和光腐蚀问题;(4)大的比表面积和介孔结构提供了大量的反应位点.因此,本研究为设计可见光型异质结催化剂提供了新思路.

Design of cobalt-based catalysts with the uniformly distributed coreshell structure for ultra-efficient activation of peroxymonosulfate for tetracycline degradation

Catalysts that can rapidly degrade tetracycline(TC)in water without introducing secondary ion pollution have always been challenging.Herein,a cobalt-based catalyst(CoO_(x)@P-C)is prepared so that CoOx quantum particles(5e10 nm)are uniformly distributed on a linear substrate,and the outer layer is covered with a shell(P-C).The quantum particles of CoO_(x) provide many active sites for the reaction,which ensures the efficient degradation effect of the catalyst,and 30 mg/L TC can be completely degraded in only 5 min.The shell of the quantum particles'outer layer can effectively reduce ions'extravasation.The combination of the shell-like structure and the linear substrate greatly enhances the catalysis's stability and ensures that the catalyst is prepared into a film for practical application.The high catalytic activity of CoO_(x)@P-C is mainly due to the following factors:(1)Uniformly distributed ultra-small nanoparticles can provide many active sites.(2)The microenvironment formed by the core-shell structure enhances not only catalytic stability but also provides the driving force to improve the reaction rate.(3)The composite of CoO_(x) and P-C core-shell structure can accelerate electron transfer and generate many reactive oxygen species in a short time,which makes TC degrade extremely rapidly.

生物硅源制备花状硅酸镁及其对放射性核素U(Ⅵ)的去除

放射性核素U(Ⅵ)的水污染问题已经成为当前核能发展亟待解决的难题之一.硅酸镁因其独特的结构特征,在水污染治理方面具有广泛的应用前景.因此,采用废弃生物硅源来代替传统硅源,制备高性能硅酸镁吸附剂具有极大的研究价值.本文通过两步法制备了高性能花状硅酸镁吸附剂,并对其进行了表征.系统研究了溶液的pH、吸附时间、吸附剂用量等因素对硅酸镁吸附行为的影响.结果表明,硅酸镁对U(Ⅵ)的吸附动力学符合拟二级速率方程;吸附和pH有很强的依赖关系;最大吸附量高达～663.7 mg/g,吸附过程符合Langmuir模型.

Constructing highly dispersed 0D Co3S4 quantum dots/2D g-C3N4 nanosheets nanocomposites for excellent photocatalytic performance

The development of noble-metal-free catalysts with high efficiency photocatalytic properties is critical to the heterogeneous catalysis. Herein, zero-dimensional(0 D) metal sulfide quantum dots/two-dimensional(2 D) g-C3N4 nanosheets(Co3S4/CNNS) nanocomposites are synthesized by a two-step method, including the ways of in-situ deposition and water bath. The highly dispersed Co3S4 quantum dots(particle size is2–4 nm) are evenly and tightly fixed on CNNS, which can be used as co-catalyst to effectively replace noble metals to improve the photocatalytic properties of CNNS. Co3S4/CNNS-900 has the apparent quantum efficiency, which is up to 7.85% at 400 nm. At the same time, the H2 evolution rate of Co3S4/CNNS-900 is 20,536.4 lmol gà1 hà1, which is 555 times than CNNS. The excellent photocatalytic performance is due to the highly dispersed Co3S4 quantum dots on 2 D CNNS, which facilitate the formation of more active sites, Co3S4/CNNS promotes the separation and migration of photogenerated carriers, shortens the migration distance of photogenerated carriers, and eventually leads to an increase of the photocatalytic performance.

Synthesis of Z-scheme g-C3N4 nanosheets/Ag3PO4 photocatalysts with enhanced visible-light photocatalytic performance for the degradation of tetracycline and dye

Graphene-like C3N4/Ag3PO4 photocatalysts are synthesized by calcination and solutions precipitating method.The obtained g-C3N4/Ag3PO4 composites display excellent photocatalytic activity for the degradation of methylene orange(MO),rhodamine B(RhB)and tetracycline(TC)under visible light irradiation.The solutions containing RhB(10 mg/L)and MO(10 mg/L)can be efficiently degraded within15 min and 30 min.Especially,nearly 80%of TC(50 mg/L)is degraded within 20 min.which are much better than those of pure g-C3N4 nanosheets and Ag3PO4,implying that strong interaction and reasonable energy band alignment in the contact interface can effectively transfer the carries.Furthermore,the g-C3N4/Ag3PO4 composites exhibit the improved stability,and only a slight decrease is observed after three recycling runs.Moreover,the impact of inorganic ions and PH values on the degradation performance is rather small.The Z-scheme photocatalytic mechanism of the g-C3N4/Ag3PO4 composites based on the active species trapping experimental is proposed.This work demonstrates the promising applications of the g-C3N4/Ag3PO4 composites in environmental issues.

Microstructure in the Semi-solid State and Mechanical Properties of AZ80 Magnesium Alloy Reheated from the As-cast and Extruded States

The multi-axial forging （MAF） process was introduced into the strain induced metal activation （SIMA） process to replace conventional forging. Microstructure evolution of MAF formed AZ80 magnesium alloy during partial remelting was investigated. Furthermore, the tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting materials treated by MAF were determined. For comparison, as-cast AZ80 magnesium alloy was also thixoextruded. The results show that the SIMA route produced ideal, fine semi-solid microstructure, in which almost completely spheroidal primary solid grains had a little amount of entrapped liquid. The microstructure of the as-cast alloy in the semi-solid state is less spheroidized compared with the MAF alloy under the similar isothermal holding conditions. With prolonged holding time, the size of the solid grain increases and the degree of spheroidization is improved in the MAF formed alloys. However, the solid grain size of the as-cast alloys decreases initially, and then increases with further increasing temperature. The tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting material produced by MAF are better than those of AZ80 magnesium alloy thixoextruded from the starting material produced by casting. The ultimate tensile strength, yield strength and elongation of the alloy thixoextruded from the starting material produced by MAF are 314 MPa, 238 MPa and 14%, respectively.

Noble metal-free core-shell CdS/iron phthalocyanine Z-scheme photocatalyst for enhancing photocatalytic hydrogen evolution

Improving the separation efficiency of photogenerated carriers and broadening the light absorption range of the photocatalyst are two important factors for improving the performance of the photocatalyst.In this paper,a new and efficient Z-scheme Cd S/iron phthalocyanine(Cd S/Fe Pc)core-shell nanostructure composite material is prepared by a simple solid-phase reaction method.There are two key points in the preparation of composite materials:one is that hydrogen bonding energy is closely connected with Fe Pc,another is that Fe Pc can be uniformly assembled on Cd S nanoparticles.The photocatalytic hydrogen evolution(PHE)of the Cd S/Fe Pc nanocomposite(73.01μmol/h)is 2.6 times higher than that of pure Cd S(26.67μmol/h).In addition,after 4 photocatalytic cycles,the PHE of the Cd S/Fe Pc composite is still 92.3%of the first cycle.There are three reasons for this situation:(1)The Z-scheme heterojunction is formed to improve the separation efficiency of photogenerated carriers;(2)Fe Pc expands the visible light absorption range of Cd S;(3)The large core-shell contact area is favorable for the separation of photo-induced carriers at the interfaces.This research is conducive to the further development of new photocatalytic materials with high efficiency,low cost and simple preparation.