Chemistry

This paper presents the specification of Universal Networking Language (UNL), a project under the auspices of the United Nations University (UNU), Tokyo and a frame work of bridging Bangla language to UNL. The mission of the UNU project is to allow people across nations to access information in Internet in their own languages. The core of the project is UNL, a language independent specification for serving as a common medium for documents in different languages. Researchers involved in this project from different countries have been developing UNL system for their respective native languages. The process basically involves i) building native language to UNL dictionary and ii) deriving language specific syntactic rules called analysis rules for parsing and translating native language corpora to UNL. In this paper we present parallel works for developing a framework for bridging Bangla to UNL showing some procedures to construct Bangla to UNL dictionary and parsing and translating Bangla sentences to UNL. As to our knowledge this is a pioneering work in Bangla.

Aqueous electrochemistry of a redox-active nonionic surfactant, a-phenothiazinylhexyl-x-hydroxyoligo(ethylene oxide) (PCPEG) and phenothiazine (PT) and its derivative, PT-labeled poly(ethylene oxide) (PT-PEO) in aqueous solution of a conventional surfactant, cetyltrimethylammonium bromide (CTAB) above its critical micelle concentration (CMC) has been studied. Cyclic voltammetric results at a glassy carbon electrode in absence and presence of urea were compared to investigate the influence of water structure modification by urea on the micellization behavior of the surfactants. The addition of urea raises the CMC of CTAB by water structure breaking effect which influences the electrochemical behavior of PT and PT-PEO in aqueous solution. The electrochemical behavior on the other hand, does not exhibit any noticeable change with added urea in aqueous solution of PCPEG. This is due to the fact that water structure modification by urea is not sufficient to upset enhanced hydrophobic interaction due to aromatic p-p-stacking interaction from PT group to disrupt PCPEG micelles to monomeric PCPEG. The comparative and contrastive features of the effect of urea to influence micellization behavior and consequent electrochemical changes for conventional and redox-active surfactants have been discussed.

My field of research is focused on bio-nanotechnology with specific aim of developing protein and DNA origami based nano-systems for applications in smart drug delivery system, vaccine development and nanomedicine. My current research focuses on to develop an artificial system made of DNA origami, protein and lipid capable for cancer therapy and developable as COVID-19 vaccine. Earlier, I developed method to demonstrate self-organization of biomolecular motor protein systems of microtubules and kinesin under cell-like confinement and their muscle-like contraction with DNA origami. I also revealed the role of reactive oxygen species on the dynamics of cytoskeletal proteins.

摘要 利用溶胶凝胶法(Sol-gel)制备纯 TiO 2 (ST)及 Ni 掺杂 TiO 2 (NT)纳米薄膜, 将其应用在光热化学循环(PTC)还原 CO 2 中进行机理研究, 并与商用 P25 (PT)进行对比. 结果表明利用 NT 进行 CO 2 还原, 每个循环得到的平均 CO 产率最 高为 5.30 μmol/g-cat, 分别是利用 ST 与 PT 得到 CO 产率的 3.13 倍与 2.28 倍. 利用扫描电子显微镜(SEM)、透射电子 显微镜(TEM)、X 射线能量色散谱(EDXS)及 X 射线衍射技术(XRD)研究样品的物质组成、晶体结构与形貌.

In the version of this article initially published, there were various label and notation errors in Figs. 2, 6 and Fig. 6 caption. In Fig. 2a, fifth column from the left, the correct label "1.0 Pt-ZnO/TiO 2 (4/1)" now replaces "1.0 Pd-ZnO/TiO 2 (4/1). " In Fig. 6a, the third column term "*O 2 *CH 3 +*H+O v " and the last column term "*O+O v +H 2 O (g) +C 2 H 2(g) " were incorrect, and have been replaced with the labels "*O 2 +*CH 3 +*H+O v " and "*O+O v +H 2 O(g)+C 2 H 6 (g)", respectively. In two instances in Fig. 6a and 6b, originally superscripted + signs in "O + ", "CH 3 (g) + " and "H + " were set on the baseline, while all instances of subscripted "(g)" were set on the baseline, and the caption was changed from "Superscript (g) represents" to read "* represents the catalytic site and (g) represents the gas phase. " The changes have been made to the html and PDF versions of the article.

Solar H 2 production is considered as a potentially promising way to utilize solar energy and tackle climate change stemming from the combustion of fossil fuels. Photocatalytic, photoelectrochemical, photovoltaic−electrochemical, solar thermochemical, photothermal catalytic, and photobiological technologies are the most intensively studied routes for solar H 2 production. In this Focus Review, we provide a comprehensive review of these technologies. After a brief introduction of the principles and mechanisms of these technologies, the recent achievements in solar H 2 production are summarized, with a particular focus on the high solar-to-H 2 (STH) conversion efficiency achieved by each route. We then comparatively analyze and evaluate these technologies based on the metrics of STH efficiency, durability, economic viability, and environmental sustainability, aiming to assess the commercial feasibility of these solar technologies compared with current industrial H 2 production processes. Finally, the challenges and prospects of future research on solar H 2 production technologies are presented.

Illisimonin A is a new sesquiterpene isolated from Illicium simonsii, and it possesses a novel 5/5/5/5/5 pentacyclic skeleton. The tricyclic skeleton of illisimonin A, tricyclo[5.2.1.01,5]decane, is presumed to be biosynthesized from allo-cedranes via a skeletal rearrangement. Herein, we report the concise synthesis of highly oxidized allo-cedranes by an intramolecular Diels–Alder reaction using ortho-benzoquinones and demonstrate the biomimetic transformation of allo-cedranes by a retro-Claisen/aldol pathway.