AgCl/BiFeO3复合光催化剂的制备及其光催化性能

采用水热法合成了BiFeO_3,使用光还原技术将AgCl沉积在BiFeO_3表面,制备了具有可见光催化活性的AgCl/BiFeO_3复合光催化剂,并利用XRD、SEM和UV-Vis DRS等分析了AgCl/BiFeO_3异质结的物相、表面结构和光响应性等性能。结果表明,AgCl的沉积不仅改善了BiFeO_3的表面结构,有效促进光生电子的迁移;而且扩宽了BiFeO_3的光响应范围,提高了BiFeO_3的可见光响应能力。以光催化降解模拟染料废水的效果评价其可见光催化性能。结果表明,Ag与Bi物质的量比为1∶2时,AgCl/BiFeO_3复合光催化剂对亚甲基蓝的降解效果最佳,光照210 min,降解率可达92.5%。AgCl/BiFeO_3复合光催化剂具有良好的光催化稳定性,循环使用5次后,降解率仍能达到80%以上。

球形钙钛矿型LaFeO_3制备及吸附动力学和热力学研究

为了获得高效处理工业废水中有机污染物的吸附剂,采用水热-焙烧法制备了球形钙钛矿型LaFeO_3,并对其物理化学特性进行了XRD、SEM和BET的表征。以典型的有机物作为模拟污染物,考察了LaFeO_3吸附有机污染物的性能。结果表明:制备的LaFeO_3半径约为5—8μm、比表面积为11.6 m^2/g的微球,在溶液初始质量浓度为30 mg/L,pH值为5,温度为25℃,吸附剂添加量为0.03 g时,LaFeO_3对酸性品红(AF)的移除率可达99%;LaFeO_3对AF的吸附符合三参数等温吸附模型和准二级动力学吸附模型,该过程是一个自发的放热物理吸附过程,且随温度升高,LaFeO_3对AF的吸附量下降。LaFeO_3是一种物理化学优良的吸附剂,具有广泛的工业应用前景。

MiR-16-5p plays an inhibitory role in human non-small cell lung cancer through Fermitin family member 2

Increasing evidence indicates that aberrant expressions of some microRNAs are associated with cancer progression.However,the roles and biological mechanisms of miRNA-16-5p in human non-small cell lung cancer(NSCLC)are not to be well studied.Here,we validated that the expression of miR-16-5p was decreased significantly in NSCLC samples and cell lines.The correlation between the clinicopathological features of NSCLC and the miR-16-5p expression showed that the expression of miR-16-5p in non-small cell lung cancer was linked with the advanced TNM stage,positive lymph node metastasis,with short overall survival(OS).Also,a negative correlation between miR-16-5p and Fermitin family member 2(FERMT2)was observed,implying there may be a potential link about their regulation.The hypothesis was further confirmed by in-silico analysis and dual-luciferase reporter assay.Moreover,we demonstrated that the transfections of miR-16-5p mimics could alter some biological characteristics of NSCLC cells remarkably accomplished by the expression variance of FERMT2 in vitro and in vivo assays.Summarily,this study demonstrated that miR-16-5p,as a tumor suppression factor in NSCLC by targeting FERMT2,could serve as one promising biomarker in the prediction for NSCLC patients.

Interfacial molecular screening of polyimide dielectric towards high-performance organic field-effect transistors

The compatibility of the gate dielectrics with semiconductors is vital for constructing efficient conducting channel for high charge transport.However,it is still a highly challenging mission to clearly clarify the relationship between the dielectric layers and the chemical structure of semiconductors,especially vacuum-deposited small molecules.Here,interfacial molecular screening of polyimide(Kapton)dielectric in organic field-effect transistors(OFETs)is comprehensively studied.It is found that the semiconducting small molecules with alkyl side chains prefer to form a high-quality charge transport layer on polyimide(PI)dielectrics compared with the molecules without alkyl side chains.On this basis,the fabricated transistors could reach the mobility of 1.2 cm^(2) V^(−1)s^(−1) the molecule with alkyl side chains on bare PI dielectric.What is more,the compatible semiconductor and dielectric would further produce a low activation energy(E_(A))of 3.01 meV towards efficient charge transport even at low temperature(e.g.,100 K,0.9 cm^(2) V^(−1)s^(−1)).Our research provides a guiding scheme for the construction of high-performance thin-film field-effect transistors based on PI dielectric layer at room and low temperatures.

Highly crystalline,highly stable n-type ultrathin crystalline films enabled by solution blending strategy toward organic single-crystal electronics

The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability.Herein,by blending with the polymers,n-type ultrathin crystalline thin film was successfully prepared by the method of meniscus-guided coating.Remarkably,the n-type crystalline films exhibit ultrathin thickness as low as 5 nm and excellent mobility of 1.58 cm^(2) V^(-1) s^(-1),which is outstanding in currently reported organic n-type transistors.Moreover,the PS layer provides a high-quality interface with ultralow defect which has strong resistance to external interference with excellent long-term stability,paving the way for the application of n-type transistors in logic circuits.

Grain boundary engineering of organic semiconductor films in organic transistors

Organicfield-effect transistors(OFETs)show great application potential in organic electronic and optoelectronicfields due to their excellent mechanicalflexibility,low cost,and solution processing.However,grain boundaries(GBs)disrupt the aggrega-tion state of organic semiconductor(OSC)films and hinder electrical performance and stability,which limits the application of OFETs.Besides,the sensitive nature of GBs is widely used in sensing,but detailed descriptions of the GBs are scarce.This review aims tofill this knowledge gap.The role of GBs and their effect on the per-formance and stability of OFETs are analyzed,followed by a detailed summary of the characterization of GBs.Then,strategies for suppressing the negative effects of GBs and utilizing the sensitive nature of GBs for application are proposed.Finally,potential research directions for GBs in OFETs are discussed.

MXene-MoS_(2)nanocomposites via chemical vapor deposition with enhanced electrocatalytic activity for hydrogen evolution

As a new paradigm of material science,two-dimensional(2D)heterostructured composites have attracted extensive interests because of combining the collective advantages and collaborative characteristics of individual building blocks.Molybdenum disulfide(MoS_(2))has demonstrated great promise as a low-cost substitute to platinum-based catalysts for electrochemical hydrogen production.However,the broad adoption of MoS_(2)is hindered by its limited number of active sites and low inherent electrical conductivity.One of the promising methods to further activate MoS_(2)is coupling engineering.Here,we demonstrate for the first time the synthesis of 2D MXene-MoS_(2)nanocomposites through chemical vapor deposition(CVD)approach,thus leading to precise design in structure type and orientation.The computational results show that nanocomposites have metallic properties.Owing to their unique 2D/2D structure,MXene-MoS_(2)nanocomposites exhibit more active catalytic sites,resulting in higher electrochemical performance,as inherited from parent excellent characteristics,and a much lower overpotential of~69 mV at a current density of 10 mA·cm^(-2) is achieved.This work paves the way to employ CVD method by coupling engineering to construct 2D nanocomposites for energy storage applications.

座壳孢及其有性型(子囊菌门)代谢产物研究进展

座壳孢及其有性型是一类重要的虫生真菌,隶属子囊菌门、粪菌纲、肉座菌目、麦角菌科,能寄生粉虱和蚧类昆虫,可开发成一种环境友好型的生物农药。座壳孢及其有性型属成员广泛分布于热带和亚热带地区,该类群物种、栖息环境和生态适应的多样性使它们的代谢产物化学结构及其生物活性彰显出多样性特点,结构和功能多样的真菌代谢产物已成为发现新药先导化合物的重要资源。虫生真菌因其独特的生活方式和多种生存环境形成了与众不同的适应寄主特性及代谢通路,明显提高获得新颖结构、显著活性的代谢产物的几率,目前已是药物重点研发的领域。在座壳孢及其有性型代谢产物研究中已报道了萜类、黄酮类、醌类、环肽和甾醇等多种化合物,并具有抗肿瘤、抗疟疾、抗菌和杀虫等多种生物活性,可在农业、工业和医药保健等方面应用。本文对近年座壳孢及其有性型代谢产物的化学成分和生物活性等方面的研究进展进行概述,为促进座壳孢及其有性型代谢产物的深入研究、开发利用和新药创制提供参考。

剩余污泥机械破碎碳源快速释放与回收技术

基于我国城市污水处理厂进水碳氮比低影响生物系统脱氮除磷效果的现状,针对传统污泥厌氧发酵产酸工艺周期长、效率低的问题,开展了剩余污泥机械破碎碳源快速释放与回收技术研究,考察了机械破碎强度与作用时间对污泥絮体结构与碳源释放的影响。结果表明,随着机械破碎强度的增加,溶解性COD的产量逐渐升高;而随着机械破碎作用时间的延长,溶解性COD的产量呈现先升高再缓慢降低的趋势,作用时间为8 min时,溶解性COD的产量达到最大,约910mg/L。激光粒度仪与环境扫描电镜分析结果显示,随着破碎强度与作用时间的增加,污泥絮体粒径逐渐变小,结构松散直至破碎,达到污泥破碎碳源释放的效果。当以产生的溶解性COD为碳源时活性污泥反硝化速率为2. 553 mgNO_3^--N/(gMLSS·h),略高于以葡萄糖为碳源时的脱氮速率。而经过机械作用后剩余污泥絮体破碎,脱氮性能基本丧失,其反硝化速率仅为0. 680 mgNO_3^--N/(gMLSS·h)。机械破碎作用可实现剩余污泥碳源的快速释放,为解决污水处理厂碳源不足与剩余污泥处置困难的问题提供了新的思路与途径。

Association between mitochondrial DNA haplotype compatibility and increased efficiency of bovine intersubspecies cloning

Reconstructed embryos derived from intersubspecies somatic cell nuclear transfer （SCNT） have poorer developmental potential than those from intrasubspecies SCNT. Based on our previous study that Holstein dairy bovine （HD） mitochondrial DNA （mtDNA） haplotype compatibility between donor karyoplast and recipient cytoplast is crucial for SCNT embryo development, we performed intersubspecies SCNT using HD as donor karyoplast and Luxi yellow heifer （LY） as recipient cytoplast according to mtDNA haplotypes determined by polymerase chain reaction- restriction fragment length polymorphism （PCR-RFLP） analysis. The results demonstrated that intersubspecies mtDNA homotype SCNT embryos had higher pre- and post-implantation developmental competence than intrasubspecies mtDNA heterotype embryos as well as improved blastocyst reprogramming status, including normal H3K9 dimethylation pattern and promoter hypomethylation of pluripotent genes such as Oct4 and Sox2, suggesting that intersubspecies SCNT using LY oocytes maintains HD cloning efficiency and may reprogram HD nuclei to develop into a normal cloned animal ultimately. Our results indicated that karyoplast-cytoplast interactions and mtDNA haplotype compatibility may affect bovine intersubspecies SCNT efficiency. This study on bovine intersubspecies SCNT is valuable for understanding the mechanisms of mtDNA haplotype compatibility between karyoplast and cytoplast impacting the bovine SCNT efficiency, and provides an alternative and economic resource for HD cloning.

Regulation of substrate surface topography on differentiation of mesenchymal stem cells

Mesenchymal stem pells(MSCs)have been extensively used in the field of tissue engineering and regenerative medicine.The effect of surface properties on the differentiation of MSCs is a very important issue for the design and fabrication of scaffolds or biomaterials.This review is mainly focused on the morphological or topographic characteristics of cell adhesion substrate,i.e.cell area and shape for individual cell,cell density and cell-cell contact for multiple cells,substrate roughnessridge width,micropillar height,nanoparticle diameter and aspect ratio of nanowire.The results from different studies were quantitativcly analyzed using comparable or unified parameters and definitions under the specific experimental conditions such as cell source,culture time,induction medium,matrix material and differentiation marker.Some interesting phenomena and properties were discovered by this integrated and systematic analysis,which might give insights into the regulatory mechanism of surface morphology or topography on MSCs differentiation.