On the vein-stiffening membrane structure of a dragonfly hind wing

Aiming at exploring the excellent structural performance of the vein-stiffening membrane structure of dragonfly hind wings, we analyzed two planar computational models and three 3D computational models with cambered corrugation based on the finite element method. It is shown that the vein size in different zones is proportional to the magnitude of the vein internal force when the wing structure is subjected to uniform out-of-plane transverse loading. The membrane contributes little to the flexural stiffness of the planar wing models, while exerting an immense impact upon the stiffness of the 3D wing models with cambered corrugation. If a lumped mass of 10% of the wing is fixed on the leading edge close to the wing tip, the wing fundamental fre- quency decreases by 10.7%-13.2%; if a lumped mass is connected to the wing via multiple springs, the wing fundamental frequency decreases by 16.0%-18.0%. Such decrease in fundamental frequency explains the special function of the wing pterostigma in alleviating the wing quivering effect. These particular features of dragonfly wings can be mimicked in the design of new-style reticulately stiffening thin-walled roof systems and flapping wings in novel intelligent aerial vehicles.     

Numerical Simulation of a Mathematical Model for Dry/Wet-Spun Nascent Hollow Fiber Membrane

NomenclatureCsh—solventconcentrationinanascenthollowfiber ( g·cm-3 )fo—dragcoefficientattheexternalsurfaceofanascenthollowfiberF( γE)—materialfunctiondefined (Eq .( 2 ) )g—gravitationalfunction ( 980cm·s-2 )G(Csh)—materialfunctiondefined (Eq .( 2 ) )Ho—thecombinedreciprocalradiiofthecurvaturesattheouterskinofthenascenthollowfiber (cm-1)L—air gapdistance (cm )Ri—innerradiusofanascenthollowfiber (cm)Ro—outerradiusofanascenthollowfiber (cm)R′o,R″o—thefirstandsecondorderderivat…     

Removal of aqueous phenol compound by vacuum membrane distillation

1.IntroductionPhenolisanimportantchemicalindustrymaterial,butitalsoaboundswithserioushazardtoenvironmentandthreatstohumanhealth.Rigidruleshavebeenmadeoutonthephenoldischargeconcentration.Researchesonthetreatmentofphenolwastewaterwerecarriedoutinvariouscountries[1-5].Membraneseparationmethodsincludingreverseosmosis,ultrafiltrationandpervaporationhaveattractedmuchattentionforphenolwastewatertreatment,withcelluloseacetate(CA)membraneemployedmostly[6].Membranedistillationisanewmembraneseparation…     

膜分离技术及其在染料生产中的应用

简述了膜分离技术的原理、装置和应用现状，介绍了反渗透、纳滤、超滤和徽滤技术的研究进展极其在染料生产中的应用。     

反渗透系统的效能影响因素分析

从膜自身的结构特性、膜系统运行的条件以及进水水质等方面,对反渗透效能具有影响作用的因素进行分析,找出具体的解决办法和适当的操作条件,使其在使用过程中增强反渗透膜的抗污染性、延长使用寿命、降低清洗的次数。     

Transportation of AIE-visualized nanoliposomes is dominated by the protein corona

Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new ‘biological identity’ and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells. Here, we employed home-made aggregation-induced-emission-visualized nanoliposomes TR4@Lipo as a model to investigate transportation with or without the protein corona by optical imaging techniques. The results show that the protein corona can change the cellular transportation mechanism of TR4@Lipo from energy-independent membrane fusion to energy-dependent endocytosis. The protein corona also modulates the intracellular distribution of loaded cargoes. This knowledge furthers our understanding of bio-nano interactions and is important for the efficient use of cationic liposomes.     

微孔防虫膜在防治天麻跳虫为害的试验研究

防虫膜防治跳虫至今未见报道,跳虫在印江土家族自治县及周边县天麻产区发生普遍而为害日益加重,对天麻的产量与品质影响很大,用显微镜观察鉴定为刺跳虫,经室内微孔防虫膜覆盖河沙厢式栽培天麻,对防虫膜防治跳虫技术进行了研究。     

浅谈漆的成膜过程及材料美感

通过对天然生漆的构成成分分析入手,更加科学的说明生漆质量好坏的决定因素,再从化学的角度详细的叙述生漆的成膜过程,最后从微观结构上分析漆材料的美感。这对我们理解生漆的材料特点更加科学化,进而更有利于我们对生漆的使用。     

The nucleotide sequence of Shigella flexneri 1A: A common Indian isolate

We report complete sequences of 2 genes of S.flexneri 1a an Indian isolate for the first time. Shigella is causative agent of shigellosis or bacillary dysentery. Genomic library was constructed by shotgun approach. Sequencing was carried out using Big Dye terminator chemistry using ABI 3730 48 capillary DNA analyzer. 170 recombinants were subjected to nucleotide sequencing. Sequence data was analyzed, of these 2 clones showed presence of complete genes out of the total clones sequenced. Annotations were done using various bioinformatics tools. Gene Sfo676 on contig SF21B11, 513 bp long codes for a protein 170 aa long with molecular weight of 18836.5 daltons. The protein is 99 % identical to S. flexneri 2a 301 and not with any other strain of Shigella. It has 7 different sites for phosphorylation, myristoylation and glycosylation. Predicted cellular localization is cytoplasmic membrane. SF0368 is another full-length gene SF0368 on contig SF69C1 is a 312 nucleotide long. It is 103 aa long with molecular weight 11394.0 daltons. Protein is 100% identical to S. flexneri 2a 301 and 99% with S. sonnei strain 046. The gene shows difference when compared with S.sonnei in mono and dinucleotide frequency as well as amino acid composition.     

蘑菇组织膜—二茂铁修饰的L-酪氨酸传感器

本文采用二茂铁作为电子传递介体,利用蘑菇组织含有丰富的酪氨酸酶,将蘑菇组织肉浆固定在二茂铁(PVC膜)修饰石墨电极上,用电流法测定L-酪氨酸浓度.研究了电极的制备和最佳实验条件,其线性响应范围为2.0×10-4～4.5×10-3 mol.L-1,响应时间小于5 min,电极寿命至少30?d,可用于实际样品分析.,A new approach for assembling amperometric mushroom pulp tissue-based membrane electrode for determination of L-tyrosine analysis is proposed. Ferrocene is used as a mediator of electron transfer between tyrosinase in mushroom tissue and a graphite electrode. The optimal operation conditions are studied. The linear response range of the biosensor is 2.0×10-4to 4.5×10-3mol.L-1 with response time of less than 5 min and lifetime of at least 30 d. The biosensor can be applied to practical sample analysis.