Preparation Of Various Kinds Research Articles

Thiol-functionalized conductive Co-MOF and its derivatives S-doped Co(OH)2 nanoflowers for high-performance supercapacitors

The low conductivity of many traditional metal–organic-framework (MOF)-based electrode limits their developments in the field of electrochemical energy storage and still of great challenge. The controllable preparation of various kinds of nanomaterials using thiol-functionalized MOF shows great prospects. In this work, a thiol-functionalized metal–organic framework sheet structure (Co-MOF/NF) on nickel foam was successfully prepared by in situ interfacial growth synthesis, which was transformed into its derivatives S-doped β-Co(OH)2 nanoflowers Co-x/NF (x = 1, 2 and 6) in different concentrations of KOH solutions through ion etching/exchange reaction. The pristine thiol-functionalized Co-MOF/NF and its derivatives Co-x/NF (x = 1, 2 and 6) nanoflower-like arrays could be used as positive electrode materials for effective supercapacitors. Among them, the transformation of the nanoflower-like Co-1/NF electrode exhibits excellent electrochemical properties with high areal capacitance (1925 ± 23 mF/cm2 at 1 mA/cm2), good rate performance, excellent conductivity and decent cycling stability. The Co-1//AC ASC device provides a high energy density of 0.176 mWh/cm2 (92.6 Wh/kg) at a power density of 0.745 mW/cm2 (392.1 W/kg). And this Co-1//AC ASC device exhibits a good cycling stability and practical application in energy storage field. This study provides a new strategy for the pristine thiol-functionalized MOF and its conversion nanostructures for energy storage applications.

Zeolitic Imidazole Framework (ZIF)-Sponge Composite for Highly Efficient U(VI) Elimination.

Herein, a zeolitic imidazole framework (ZIF-67) composite was prepared by a rapid, simple and inexpensive situ hybridization technique applying polyurethane sponge (PU) as support, which was designated as ZIF-67-PU. The ZIF-67 nanoparticle was successfully supported on the surface of sponge skeletons mainly through electrostatic attraction as well as probable π-π stacking interactions with PAM modification of the sponge. The resultant ZIF-67-PU exhibited a remarkably enhanced U(VI) elimination capacity of 150.86 mg∙g-1 on the basis of the Langmuir isotherm model, in comparison to pristine sponge. Additionally, the mechanism for U(VI) elimination was mainly achieved through the complex reaction between C-N(H)/-OH groups in ZIF-67 and U(VI), based on XPS investigations. ZIF-67-PU represents a simple, feasible and low-cost disposal option for preparing ZIF-coated sponges of any shape that can enhance the U(VI) elimination capacity. Furthermore, this approach can be widely applied to the preparation of various kinds of MOF-sponges through this situ hybridization technique.

Pharmaceutico-Analytical study of Karaviradya taila

Introduction: Sneha kalpana (oleaginous preparations) is commonly prescribed Ayurvedic dosage form and it is the preparation of various kinds of medicated oils and ghee. Karaviradya taila is medicated oil preparation used externally in the form of abhyanga (massage) for lomashatana (depilation). Objectives: To prepare and carry out the physico-chemical analysis of karaviradya taila. Materials and Methods: Karaviradya taila was prepared by general method of taila kalpana i.e ¼:1:4 and analytical study like organoleptic characters and physico- chemical parameters were carried out based on the references available in the laboratory guide for the analysis of Ayurveda and Siddha formulation. Results and Discussion: The total oil obtained was 85% and the loss was 15%. Organoleptic characters of karaviradya taila showed translucent green viscous liquid with alkaline odor, Physico- chemical parameters like pH, specific gravity, viscosity, total suspended solids, and refractive index were tested. The increased Saponification value of karaviradya taila indicates the rate of absorption, low acid value of karaviradya taila indicates less chance of decomposition of taila. Evaporation of moisture contents in karaviradya taila leads to the decrease in rancidity factors. Peroxide value and iodine value of karaviradya taila indicates the primary oxidation. Conclusion: Karaviradya taila is a sneha kalpana mainly indicated for loma shatana (depilation). Local applications is beneficial because they are quickly absorbable, protect the skin and promotes percutaneous absorption of incorporated drug. The results of pharmaceutical and analytical study of karaviradya taila can be considered as the preliminary standards for the preparation of karaviradya taila.
 
 Keywords: Lomashatana, Karaviradyataila, Bahirparimarjana chikitsa, Sneha kalpana, Depilation, Hair Removal.

P-doped PANI/AgMWs nano/micro coating towards high-efficiency flame retardancy and electromagnetic interference shielding

With the rapid development of 5G technology, functional coatings with both high-efficiency flame retardancy and electromagnetic interference shielding (EMI) are urgently needed, while traditional inefficient methods have encountered bottlenecks. Herein, we demonstrate an eco-friendly and multifunctional nano/micro coating constructed by biomass phytic acid (PA) induced polymerization and self-assembly of polyaniline (PANI) nanoparticles and dip-coating of silver microwires (AgMWs). In this design, PA with high flame-retardant efficiency is smartly doped into PANI to achieve P-N synergistic flame retardancy and improve electrical conductivity of PANI simultaneously. Consequently, under the coaction of AgMWs, P-doped PANI nanoparticles, as well as unique continuous micro-nano structures, the nano/micro coating can endow commercial polyurethane (PU) foams with outstanding EMI shielding performance (∼51 dB in X-band). Meanwhile, the coated PU foam exhibits high flame retardancy due to the P-N synergistic effect of PA/PANI, which self-extinguishes immediately after ignition during the UL-94 vertical burning test, shows a high limiting oxygen index (LOI) value of 34.8%, and exhibits a 50.7% lower peak heat release rate compared with pure PU foam. Further, the functional nano/micro coating with three-dimensional and highly porous structure makes the foam thermally insulating and infrared stealthing. The eco-friendliness and simplicity of this method and its successful application in commercial PU foam make it potentially applicable for the preparation of various kinds of multifunctional EMI shielding materials.

Abramchik and Ostrovsky: the struggle for leadership among the Belarusian post-war emigration

The post-war Belarusian emigration, both in Europe and in the United States, was divided into two main groups: the supporters of the President of the Belarusian Central Rada R. K. Ostrowski (Astrouski) and the Chairman of the BNR Rada N. S. Abramchyk. The declassified CIA documents indicate that this was not just a rivalry for the right to speak and act on behalf of the entire Belarusian emigration, but also to receive substantial dividends from close cooperation with the American intelligence agency in the implementation of plans to destabilize the situation in Belarus through the preparation of various kinds of espionage and subversive operations, up to the direct delivery of agents to the territory of the BSSR in the 1950s, as well as in information and propaganda work against the Soviet Belarus. This confrontation took various forms: from accusations of direct collaboration with the Nazis during the war (Ostrowski) to the self-appointment as the head of the Belarusian Folk Republic (Abramchyk). The visions of the future of free Belarus and its foreign policy between these actors differed, as well as the means and methods of struggle for the liberation of the Belarusian people from the communist system. At the same time, both Abramchyk and Ostrowski understood well that in order to strengthen their positions among the Belarusian emigration, close relations with those who built and financed the anti-Soviet policy of the West during the Cold War were important. First of all, it was about the American intelligent services. And here Abramchyk won an obvious victory, and Ostrowski’s main former comrades-in-arms were soon going to move to his camp.

A hybrid material composed of reduced graphene oxide and porous carbon prepared by carbonization of a zeolitic imidazolate framework (type ZIF-8) for voltammetric determination of chloramphenicol

Porous carbon was prepared from a zeolitic imidazolate framework (type ZIF-8) by carbonization at 800°C (Z-800). A hybrid material was then obtained by direct co-electrodeposition of Z-800 with graphene oxide (Z-800/rGO). Z-800 is N-doped with good electrical conductivity and displays electrocatalytic activity. Z-800 readily undergoes mass transfer and also prevents graphene to agglomerate during electroanalysis. The hybrid was placed on a glassy carbon electrode (GCE) to obtain an electrochemical sensor for chloramphenicol (CAP) detection. Under the optimized conditions, the response of the modified GCE (typically measured at a low potential of -0.07V vs. Ag/AgCl) is linear in the 1 to 180μM CAP concentration range with a 0.25μM detection limit (S/N = 3). In our preception, the method has a wide scope in that it may be applied to the preparation of various kinds of other (doped) porous carbon/rGO composites for use in (bio)chemical sensors. Graphical abstract Schematic presentation of the preparation process of the materials and the electrochemical detection of chloramphenicol.

Evaluation of Tensile and Thermal Behavior Analysis of Nano Carbon Fiber Reinforced Polymer Composite

Today a lot of research work is performed throughout the world on the use of natural fibers as a strengthening material introduced in the preparation of various kinds of composites, and also the use of natural fiber/polymer composites in civil and mechanical engineering fields are playing very important role due to its usage of natural resource and its properties. From the current journal, we have recently found NFRPC fibers which are extracted from NFRPC plants by involving hard physical work. In this journal, the tensile components of the six to seven months NFRPCare analyzed through various tests such as FTIR, XRD, SEM, THERMO GRAVIMETRIC ANALYSE and match with other available conventional all-natural fibers, and also examine the chemical qualities of NFRPC. The fiber of NFRPC has a high wax content, so it's easy to bind with materials like resin. SEM analyze also signifies the presence of voids on the interior surface of the fiber material. and the results show that the NFRPC provides good Tensile and Thermal properties.

Nanomaterials for cancer therapies

AbstractCancer is one of the most deadly diseases in the world. In recent years, nanotechnology, as a unique technology, has been comprehensively applied in the therapy of cancer through diagnosis, imaging and theranostics. Additionally, with the emergence of advanced biomaterials which are capable of being applied in biomedical, research in cancer nanotechnology has made significant progress. Particularly, nanomaterials with dimensions below several hundred nanometers are intensively studied among these advanced biomaterials. In past decades, a number of organic and inorganic nanomaterials have emerged as novel tools for cancer diagnostics and therapeutics due to their unique characteristics, like their solubilization effect, drug protection, passive/active tumor targeting, controlled release of drugs which result in enhanced anticancer efficacy while reducing the side effects. In this review, we first provide a brief description of the key properties of nanomaterials, such as nanoparticle (NP) size, surface properties and tumor targeting. The major goal of this review is to summarize the achievements that have been made in the development of the application of nanomaterials for cancer therapies, along with a short description of their general characteristics and preparation of various kinds of nanoparticles.

(Invited) Synthesis of Ordered Semiconductor Nanostructures for Energy Conversion Using Anodic Porous Alumina

Efficient synthesis of the ordered nanostructures of semiconductors is important issue to be solved for the preparation of the photo-energy conversion systems with high efficiency [1]. For the effective preparation of the ordered nanostructures of semiconductors, the use of the naturally occurring ordered nanomaterials is promising for the synthesis due to its capability of the preparation of ordered nanostructures with high efficiency. Among them, anodic porous alumina, which is formed by anodization of Al in acidic electrolyte, is one of promising material due to ist precisely controllable geometrical nanostructures [2]. In the present report, the synthesis of the ordered nanostructures of semiconductors using anodic porous alumina templates will be described. The template synthesis using highly ordered anodic porous alumina allows the preparation of ordered nanostructures of the semiconductors. In addition, the application of the highly ordered anodic porous alumina with reduced hole intervals (~25 nm) and hole sizes (~10 nm) prepared under the low voltage anodization [3] generated the ordered structures of semiconductors with small dimensions. In the experiment, semiconductor (ZnO [4,5], CdS) nanorod arrays were prepared by electrochemical or hydrothermal synthesis of semiconductors using anodic porous alumina templates. The geometrical structure of the obtained nanorod arrays of semiconductors could be precisely controlled based on the ordered structures of anodic porous alumna. The synthesis of the nanorod arrays on the conducting substrates (ITO etc.) could provide the current collection electrodes with large surface area. The present process will be used for the preparation of nanostructures of semiconductors, which are required for the preparation of various kinds of photoenergy conversion systems with high efficiency, such as organic photovoltaic solar cells [6]. 1. T. Shinagawa, S. Watase, M. Izaki, Cryst. Growth Des., 11, 5533 (2011). 2. H. Masuda and K. Fukuda, Science, 268, 1466 (1995). 3. H. Masuda, K. Takenaka, T. Ishii, K. Nishio, Jpn. J. Appl. Phys., 45, L1165 (2006). 4. M. Izaki, T. Omi, Appl. Phys. Lett., 98, 2439 (1996). 5. T. Özdal, R. Taktakoğlu, H. Özdamar, M. Esen, D. K. Takҫi, H. Kavak, Thin Solid Films, 592, 143 (2015). 6. B. Kippelen, J.-L. Brédas, Energy Environ. Sci., 2, 251 (2009).

Surfactant-free dispersion polymerization as an efficient synthesis route to a successful encapsulation of nanoparticles

We propose a new method based on surfactant-free aqueous/alcoholic dispersion polymerization, which enables the encapsulation of nanoparticles in polymer latex. The mechanism of this approach is investigated in the preparation of carbon black (CB) incorporated polystyrene (PS) composite latex. First, commercial grade MOGUL® L CB is grafted with reactive silane coupling agents through a sol–gel reaction and is finely dispersed in the polar medium with dissolved monomer. Then, the ionic initiator is added to the system to start the polymerization. The reactive functional groups introduced onto the CB surface enable its participation into the nucleation and surface polymerization, leading to the well-defined CB-encapsulated PS composite latex structure. The efficiency of CB nanoparticle encapsulation is correlated to the extent of association/aggregation among the nuclei and CB nanoparticles during nucleation, which is found to be proportional to the polarity of the medium. The thickness of the polymer shell is controlled by tuning the weight ratio between carbon black and the monomer. Successful encapsulation of CB particles was demonstrated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). It is demonstrated that this new polymerization technique can be universally utilized for the preparation of various kinds of nanoparticle-encapsulated polymer composite latexes up to micron size with a high loading of nanoparticles. The effect of various factors on this new approach is investigated, and a possible mechanism is also presented.

Preparation of various kinds of copper sulfides in a facile way and the enhanced catalytic activity by visible light

Various kinds of copper sulfides (CuS, a mixture of Cu7S4–CuS and Cu9S5) were synthesized by simply adjusting the amount of copper chloride and sodium sulfide in a solvothermal process. The different molar ratios of copper chloride and sodium sulfide result in the formation of different kinds of copper sulfides with various morphologies, such as tiny particle, hexagonal plate and octahedron. The products were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. And the optical properties of the products were recorded by means of UV-Vis absorption and photoluminescence spectroscopy. Moreover, due to the presence of visible light, we found that the catalytic activities of the products for oxidation and decomposition of Rhodamine B with the assistance of hydrogen peroxide were enhanced, and the degradation efficiency of RhB was increased from 40% to 98% in 15 minutes at room temperature.

Purification and Characterization of an NADH-Dependent Alcohol Dehydrogenase fromCandida marisfor the Synthesis of Optically Active 1-(Pyridyl)ethanol Derivatives

A novel (R)-specific alcohol dehydrogenase (AFPDH) produced by Candida maris IFO10003 was purified to homogeneity by ammonium sulfate fractionation, DEAE-Toyopearl, and Phenyl-Toyopearl, and characterized. The relative molecular mass of the native enzyme was found to be 59,900 by gel filtration, and that of the subunit was estimated to be 28,900 on SDS-polyacrylamide gel electrophoresis. These results suggest that the enzyme is a homodimer. It required NADH as a cofactor and reduced various kinds of carbonyl compounds, including ketones and aldehydes. AFPDH reduced acetylpyridine derivatives, β-keto esters, and some ketone compounds with high enantioselectivity. This is the first report of an NADH-dependent, highly enantioselective (R)-specific alcohol dehydrogenase isolated from a yeast. AFPDH is a very useful enzyme for the preparation of various kinds of chiral alcohols.

A General Electrochemical Strategy for Synthesizing Charge‐Transfer Complex Micro/Nanowires

AbstractUniversal strategies for synthesizing one‐dimensional organic nanomaterials are of fundamental importance in the development of more flexible, cheaper and lighter electronics. Charge‐transfer (CT) complexes, the major kind of organic conductors, are in the long‐term attractive materials owing to their unique crystal structures and conductive properties. In this article, a general strategy for the synthesis of CT complex micro/nanowires based on the localized nanoelectrochemistry using tiny carbon nanotube (CNT) electrodes is presented. This strategy is successfully demonstrated over 12 typical CT complexes, and a general rule for the preparation of various kinds of CT complex micro/nanowires is summarized. The CT complex micro/nanowires thus synthesized have high aspect ratios and long lengths as compared with traditional macroscopic planar electrodes, originating from the one‐dimensional structural feature with fewer or no defects and the ultrasmall surface area of the CNT. This work provides a more versatile material basis for the fundamental and application studies of low‐dimensional organic conductor materials.

Establishment of Chemical Preparation Methods and Development of an Automated Reduction System for AMS Sample Preparation at Kigam

Many previous studies on the sample preparation of various kinds of radiocarbon dating samples by accelerator mass spectrometry (AMS) have been examined at KIGAM (Korea Institute of Geoscience and Mineral Resources) and our own procedures have been established. Furthermore, an automated reduction system has been developed. The volume of the reduction region was minimized to improve the reduction yield, and air-actuated pneumatic valves and solenoid arrays were used for computer control of the system. Operation of all the valves and vacuum pumps and signals from the temperature sensors and pressure gauges were interfaced to a personal computer with an A/D board. A computer program was also developed to perform automatic operation of the reduction system. This system consistently shows a higher reduction yield than 90%. The reduction time of the system is currently 140 min.

Facile Synthesis of Degradable Gels by Oxygen Cross-Linking of Polymers Including a Dienyl Group on Their Side Chain or at Chain Ends

We have demonstrated a facile method for the synthesis of a new kind of degradable gel, which is prepared by the introduction of a dienyl group into the side chains or the chain ends of conventional polymers such as poly(acrylic acid), poly(ethylene oxide), poly(2-hydroxyethyl methacrylate), and poly(vinyl alcohol) and the subsequent radical copolymerization of the diene with oxygen in the presence of a radical initiator. The obtained gels contain the polyperoxy units as the cross-linking points and readily degrade upon heating. Sorbic derivatives including epoxy and anhydride functional groups are used as reagents for the dienyl functionalization of the precursor polymers with a high efficiency. The heat of degradation of the polymer gels synthesized in this study is much smaller than that of the previously reported polyperoxides as degradable polymers and gels. This method is applied to the preparation of various kinds of polymer networks programmed for degradation after temporary use.

New synthetic method for cycloalkanedione

Four kinds of cycloalkanedione were prepared from bis-benzimidazole methiodide salt and bis-Grignard reagent, the addition-hydrolysis reaction of bis-benzimidazole methiodide salt with bis-Grignard reagent is reported and a novel method for the preparation of various kinds of cycloalkanedione is provided.

ChemInform Abstract: A Highly Efficient Kinetic Resolution of γ‐ and β‐Trimethylsilyl Secondary Allylic Alcohols by the Sharpless Asymmetric Epoxidation.

Abstract Kinetic resolution of γ- and β-trimethylsilyl secondary allylic alcohols proceeds with very large and synthetically satisfactory rate differences for the two enantiomers, respectively, thus providing a convenient and widely applicable method for preparation of various kinds of homochiral compounds.

ChemInform Abstract: Building Blocks for the Preparation of Monofluoro Organic Compounds

The methodologies employed in the use of building blocks in the synthesis of various kinds of monofluoro molecules are reviewed in light of recent increasing interest and demand for organofluorine compounds in synthetic and biological chemistry. The building blocks were chosen with the following two criteria in mind : ease of preparation or commercial availability and wide applicability of the compounds derived therefrom.This article is organized into four sections : i) the necessity of and requirement for building blocks, ii) the building blocks for the preparation of various kinds of vinyl fluorides, iii) the building blocks for the preparation of various kinds of alkyl fluorides, and iv) versatile and practical building blocks with wide synthetic applicability.

有機モノフルオロ化合物合成のための合成ブロック

The methodologies employed in the use of building blocks in the synthesis of various kinds of monofluoro molecules are reviewed in light of recent increasing interest and demand for organofluorine compounds in synthetic and biological chemistry. The building blocks were chosen with the following two criteria in mind : ease of preparation or commercial availability and wide applicability of the compounds derived therefrom.This article is organized into four sections : i) the necessity of and requirement for building blocks, ii) the building blocks for the preparation of various kinds of vinyl fluorides, iii) the building blocks for the preparation of various kinds of alkyl fluorides, and iv) versatile and practical building blocks with wide synthetic applicability.

A highly efficient kinetic resolution of γ- and β- trimethylsilyl secondary allylic alcohols by the sharpless asymmetric epoxidation

Kinetic resolution of γ- and β-trimethylsilyl secondary allylic alcohols proceeds with very large and synthetically satisfactory rate differences for the two enantiomers, respectively, thus providing a convenient and widely applicable method for preparation of various kinds of homochiral compounds.