keyword
MENU ▼
Read by QxMD icon Read
search

Rh system

keyword
https://www.readbyqxmd.com/read/28513335/tio2-uv-assisted-rhodamine-b-degradation-putative-pathway-and-identification-of-intermediates-by-uplc-ms
#1
Tahir Rasheed, Muhammad Bilal, Hafiz M N Iqbal, Syed Zakir Hussain Shah, Hongbo Hu, Xuehong Zhang, Yongfeng Zhou
The present study was designed to evaluate the photocatalytic degradation of Rhodamine B (Rh-B) in a self-assembled TiO2 assisted system under UV light irradiation. Chemical oxygen demand (COD), total organic carbon (TOC), and high-performance liquid chromatography (HPLC) analyses confirmed the elevated Rh-B degradation level. A stepwise meticulous breakdown pathway based on the ultra-performance liquid chromatography coupled with electrospray ionization mass spectrometry (UPLC-MS) is proposed. Results demonstrated that the degradation of Rh-B mainly occurred via N-de-ethylation process, and N-de-ethylated intermediate products were further oxidized into acids and alcohols...
May 17, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28506870/development-of-solid-sedds-vii-effect-of-pore-size-of-silica-on-drug-release-from-adsorbed-self-emulsifying-lipid-based-formulations
#2
Suhas G Gumaste, Abu T M Serajuddin
PURPOSE: Lipid-based self-emulsifying drug delivery systems (SEDDS) are usually liquids, and they can be converted into solid dosage forms by adsorbing onto silicates. However, most commercially available silicates are mesoporous with small pore sizes of 1 to 50nm that lead to incomplete emulsification of SEDDS inside the pores and thus incomplete drug release. The objective of this study was to investigate the impact of silica pore size on the extent of drug release from SEDDS solidified by adsorbing onto macroporous silicas with different pore sizes...
May 12, 2017: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28500759/a-monte-carlo-model-for-mean-glandular-dose-evaluation-in-spot-compression-mammography
#3
Antonio Sarno, David R Dance, Ruben E van Engen, Kenneth C Young, Paolo Russo, Francesca Di Lillo, Giovanni Mettivier, Kristina Bliznakova, Baowei Fei, Ioannis Sechopoulos
PURPOSE: To characterize the dependence of normalized glandular dose (DgN) on various breast model and image acquisition parameters during spot compression mammography and other partial breast irradiation conditions, and evaluate alternative previously-proposed dose-related metrics for this breast imaging modality. METHODS: Using Monte Carlo simulations with both simple homogeneous breast models and patient-specific breasts, three different dose related metrics for spot compression mammography were compared: the standard DgN, the normalized glandular dose to only the directly irradiated portion of the breast (DgNv), and the DgN obtained by the product of the DgN for full field irradiation and the ratio of the mid-height area of the irradiated breast to the entire breast area (DgNM )...
May 13, 2017: Medical Physics
https://www.readbyqxmd.com/read/28488856/light-driven-hydrogen-generation-from-microemulsions-using-metallosurfactant-catalysts-and-oxalic-acid
#4
Husain N Kagalwala, Danielle N Chirdon, Isaac N Mills, Nikita Budwal, Stefan Bernhard
A unique microemulsion-based photocatalytic water reduction system is demonstrated. Iridium- and rhodium-based metallosurfactants, namely, [Ir(ppy)2(dhpdbpy)]Cl and [Rh(dhpdbpy)2Cl2]Cl (where ppy = 2-phenylpyridine and dhpdbpy = 4,4'-diheptadecyl-2,2'-bipyridine), were employed as photosensitizer and proton reducing catalyst, respectively, along with oxalic acid as a sacrificial reductant in a toluene/water biphasic mixture. The addition of 1-octylamine is proposed to initiate the reaction, by coupling with oxalic acid to form an ion pair, which acts as an additional surfactant...
May 10, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28485604/rh-wudaphos-catalyzed-asymmetric-hydrogenation-of-sodium-%C3%AE-arylethenylsulfonates-a-method-to-access-chiral-%C3%AE-arylethylsulfonic-acids
#5
Xuguang Yin, Caiyou Chen, Xiu-Qin Dong, Xumu Zhang
A highly enantioselective hydrogenation of various sodium α-arylethenylsulfonates catalyzed by Rh/chiral ferrocenyl bisphosphorus ligand (Wudaphos) was successfully developed to construct a series of chiral α-arylethylsulfonic acids in the presence of CF3SO3H with full conversion and good to excellent enantioselectivity (>99% conversion, up to 96% ee) under mild reaction conditions for the first time. Moreover, the control experiment results showed that the non-covalent ion pair interaction between the α-arylethenylsulfonic acid and the Wudaphos ligand plays an important role in this asymmetric hydrogenation system...
May 9, 2017: Organic Letters
https://www.readbyqxmd.com/read/28472889/asymmetric-transfer-hydrogenation-of-hetero-arylketones-with-tethered-rh-iii-tsdpen-complexes-scope-and-limitations
#6
Longsheng Zheng, Quentin Llopis, Pierre-Georges Echeverria, Charlène Férard, Gérard Guillamot, Phannarath Phansavath, Virginie Ratovelomanana-Vidal
A series of new tethered Rh(III)/Cp* complexes containing the TsDPEN ligand has been prepared, characterized and evaluated in the asymmetric transfer hydrogenation of a wide range of (hetero)aryl ketones. The reaction was performed under mild conditions with the formic acid/triethylamine (5:2) system as the hydrogen source and provided enantiomerically enriched alcohols with good yields and high to excellent enantioselectivities. Although the nature of the substituents on the phenyl tethering ring did not alter the stereochemical outcome of the reaction, complexes bearing electron-donating groups exhibited a higher catalytic activity than those having electron-withdrawing groups...
May 5, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28453254/gene-transfection-mediated-by-catiomers-requires-free-highly-charged-polymer-chains-to-overcome-intracellular-barriers
#7
Lindomar J C Albuquerque, Carlos E de Castro, Karin A Riske, Maria C Carlan da Silva, Paulo I R Muraro, Vanessa Schmidt, Cristiano Giacomelli, Fernando C Giacomelli
The prospective use of the block copolymers poly(ethylene oxide)113-b-poly[2-(diethylamino)ethyl methacrylate]50 (PEO113-b-PDEA50) and poly[oligo(ethylene glycol)methyl ether methacrylate]70-b-poly[oligo(ethylene glycol)methyl ether methacrylate10-co-2-(diethylamino)ethyl methacrylate47-co-2-(diisopropylamino)ethyl methacrylate47] (POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47)) as nonviral gene vectors was evaluated. The polymers are able to properly condense DNA into nanosized particles (RH ≈ 75 nm), which are marginally cytotoxic and can be uptaken by cells...
May 5, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28451201/sequential-catalysis-exploiting-a-single-rhodium-i-catalyst-to-promote-an-alkyne-hydroacylation-aryl-boronic-acid-conjugate-addition-sequence
#8
Maitane Fernández, Matthias Castaing, Michael C Willis
We demonstrate that a single Rh(i) complex can promote two mechanistically distinct C-C bond-forming reactions - alkyne hydroacylation and aryl boronic acid conjugate addition - to deliver substituted ketone products from the controlled assembly of three readily available fragments. This is a rare example of a Rh(i)/Rh(iii) cycle and a redox neutral Rh(i) cycle being promoted by a single catalyst. The process is broad in scope, allowing significant variation of all three reaction components. Incorporation of an enantiomerically pure bis-phosphine ligand renders the process enantioselective...
January 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28437119/synthesis-of-naphthoquinolizinones-through-rh-iii-catalyzed-double-c-sp-2-h-bond-carbenoid-insertion-and-annulation-of-2-aryl-3-cyanopyridines-with-%C3%AE-diazo-carbonyl-compounds
#9
Beibei Zhang, Bin Li, Xinying Zhang, Xuesen Fan
An unprecedented Rh(III)-catalyzed double C(sp(2))-H bond carbenoid insertion and annulation of 2-aryl-3-cyanopyridines with α-diazo carbonyl compounds is presented. Through this cascade reaction, a series of naphthoquinolizinone derivatives with a large π-system were efficiently prepared. The reactions could selectively afford naphthoquinolizinones with either an amine or an amide unit attached on the 11-position depending on the nature of the solvent and the additive used. Compared with literature methods, this is a more efficient, convenient, and atom-economic way to provide polycyclic heteroaromatic compounds through direct π-extension of simple aromatics via inert C-H bond activation and functionalization...
May 5, 2017: Organic Letters
https://www.readbyqxmd.com/read/28436523/mechanistic-insights-into-the-selective-cyclization-of-indolines-with-alkynes-and-alkenes-to-produce-six-and-seven-membered-1-7-fused-indolines-via-rh-iii-catalysis-a-theoretical-study
#10
Lingli Han, Xinyu Zhang, Xingdong Wang, Fengyue Zhao, Shaojing Liu, Tao Liu
The coupling reaction mechanisms of the Rh(iii)-catalyzed redox-neutral C7-selective aryl C-H functionalization of indolines with alkynes and alkenes have been theoretically investigated with the aid of the density functional theory (DFT) calculations. Our calculation results indicate that the active catalyst in this system is the cationic species [Cp*Rh(OAc)](+) (2cat) instead of the neutral species Cp*Rh(OAc)2 (1cat). The origin of forming different products associated with using different coupling partners was also rationalized in detail...
May 10, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28429455/base-controlled-completely-selective-linear-or-branched-rhodium-i-catalyzed-c-h-ortho-alkylation-of-azines-without-preactivation
#11
Gaël Tran, Kevin D Hesp, Vincent Mascitti, Jonathan A Ellman
A [Rh(I) ]/bisphosphine/base catalytic system for the ortho-selective C-H alkylation of azines by acrylates and acrylamides is reported. This catalytic system features an unprecedented complete linear or branched selectivity that is solely dependent on the catalytic base that is used. Complete branched selectivity is even achieved for ethyl methacrylate, which enables the introduction of a quaternary carbon center. Excellent functional group compatibility is demonstrated for both linear and branched alkylations...
April 21, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28422264/rhodium-catalyzed-addition-of-sulfonyl-hydrazides-to-allenes-regioselective-synthesis-of-branched-allylic-sulfones
#12
Vahid Khakyzadeh, Yu-Hsuan Wang, Bernhard Breit
A rhodium-catalyzed regioselective addition of sulfonyl hydrazides to allenes is reported. With Rh(i)/DPEphos/benzoic acid as the catalyst system, branched allylic sulfones can be obtained, in good to excellent yields and regioselectivities.
April 19, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28414337/development-of-an-incoherent-broad-band-cavity-enhanced-aerosol-extinction-spectrometer-and-its-application-to-measurement-of-aerosol-optical-hygroscopicity
#13
Weixiong Zhao, Xuezhe Xu, Bo Fang, Qilei Zhang, Xiaodong Qian, Shuo Wang, Pan Liu, Weijun Zhang, Zhenzhu Wang, Dong Liu, Yinbo Huang, Dean S Venables, Weidong Chen
We report on the development of a blue light-emitting-diode-based incoherent broad-band cavity-enhanced absorption spectroscopy (IBBCEAS) instrument for the measurement of the aerosol extinction coefficient at λ=461  nm. With an effective absorption path length of 2.8 km, an optimum detection limit of 0.05  Mm<sup>-1</sup> (5×10<sup>-10</sup>  cm<sup>-1</sup>) was achieved with an averaging time of 84 s. The baseline drift of the developed spectrometer was about ±0...
April 10, 2017: Applied Optics
https://www.readbyqxmd.com/read/28403850/rationale-and-design-of-a-multicenter-placebo-controlled-double-blind-randomized-trial-to-evaluate-the-effect-of-empagliflozin-on-endothelial-function-the-emblem-trial
#14
RANDOMIZED CONTROLLED TRIAL
Atsushi Tanaka, Michio Shimabukuro, Yosuke Okada, Isao Taguchi, Minako Yamaoka-Tojo, Hirofumi Tomiyama, Hiroki Teragawa, Seigo Sugiyama, Hisako Yoshida, Yasunori Sato, Atsushi Kawaguchi, Yumi Ikehara, Noritaka Machii, Tatsuya Maruhashi, Kosuke R Shima, Toshinari Takamura, Yasushi Matsuzawa, Kazuo Kimura, Masashi Sakuma, Jun-Ichi Oyama, Teruo Inoue, Yukihito Higashi, Shinichiro Ueda, Koichi Node
BACKGROUND: Type 2 diabetes mellitus (T2DM) is characterized by systemic metabolic abnormalities and the development of micro- and macrovascular complications, resulting in a shortened life expectancy. A recent cardiovascular (CV) safety trial, the EMPA-REG OUTCOME trial, showed that empagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor, markedly reduced CV death and all-cause mortality and hospitalization for heart failure in patients with T2DM and established CV disease (CVD)...
April 12, 2017: Cardiovascular Diabetology
https://www.readbyqxmd.com/read/28399420/dietary-rose-hip-exerts-antiatherosclerotic-effects-and-increases-nitric-oxide-mediated-dilation-in-apoe-null-mice
#15
Michele Cavalera, Ulrika Axling, Catarina Rippe, Karl Swärd, Cecilia Holm
Atherosclerosis is a disease in which atheromatous plaques develop inside arteries, leading to reduced or obstructed blood flow that in turn may cause stroke and heart attack. Rose hip is the fruit of plants of the genus Rosa, belonging to the Rosaceae family, and it is rich in antioxidants with high amounts of ascorbic acid and phenolic compounds. Several studies have shown that fruits, seeds and roots of these plants exert antidiabetic, antiobesity and cholesterol-lowering effects in rodents as well as humans...
June 2017: Journal of Nutritional Biochemistry
https://www.readbyqxmd.com/read/28395388/results-of-a-modular-femoral-revision-system-before-and-after-taper-roller-hardening-in-total-hip-arthroplasty
#16
Dean J Marshall, Keith R Berend, Michael J Morris, Joanne B Adams, Adolph V Lombardi
INTRODUCTION: Modular component options can aid in addressing complex femoral reconstructions in total hip arthroplasty (THA) by allowing for customization of version control and proximal to distal sizing. However, component breakage at the modular junction has occurred, particularly in the presence of poor bone stock. A taper roller hardening (RH) process was developed to strengthen the modular junction to reduce breakage. The purpose of this study is to review THA patients before and after taper roller hardening to compare stem survival and frequency of breakage...
April 11, 2017: Surgical Technology International
https://www.readbyqxmd.com/read/28394617/understanding-the-impact-of-water-on-the-miscibility-and-microstructure-of-amorphous-solid-dispersions-an-afm-lcr-and-tem-edx-study
#17
Na Li, Christopher J Gilpin, Lynne S Taylor
Miscibility is critical for amorphous solid dispersions (ASDs). Phase-separated ASDs are more prone to crystallization, and thus can lose their solubility advantage leading to product failure. Additionally, dissolution performance can be diminished as a result of phase separation in the ASD matrix. Water is known to induce phase separation during storage for some ASDs. However, the impact of water introduced during preparation has not been as thoroughly investigated to date. The purpose of this study was to develop a mechanistic understanding of the effect of water on the phase behavior and microstructure of ASDs...
April 19, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28390289/lenvatinib-an-oral-multi-kinases-inhibitor-associated-hypertension-potential-role-of-vascular-endothelial-dysfunction
#18
Daisuke Sueta, Koichi Suyama, Aiko Sueta, Noriaki Tabata, Takayoshi Yamashita, Mai Tomiguchi, Takashi Takeshita, Mutsuko Yamamoto-Ibusuki, Eiichiro Yamamoto, Yasuhiro Izumiya, Koichi Kaikita, Yutaka Yamamoto, Seiji Hokimoto, Hirotaka Iwase, Kenichi Tsujita
BACKGROUND AND AIMS: Lenvatinib (Lenvima(®)), an oral multi-kinase inhibitor, is effective in the treatment of differentiated thyroid carcinomas (DTCs). A severe adverse effect of lenvatinib is hypertension, thus limiting its use as an anti-cancer treatment. Although the pathogenesis of hypertension is generally assumed to involve microvascular bed reduction and an increase in peripheral vascular resistance due to a decrease in nitrogen oxide (NOx) production after vascular endothelial growth factor (VEGF) inhibition, the effects of hypertension on vascular endothelial function in actual patients remain unclear...
May 2017: Atherosclerosis
https://www.readbyqxmd.com/read/28383287/successful-synthesis-and-thermal-stability-of-immiscible-metal-au-rh-au-ir-andau-ir-rh-nanoalloys
#19
Yury Shubin, Pavel Plyusnin, Marat Sharafutdinov, Evgenia Makotchenko, Sergey Korenev
We successfully prepared face-centred cubic nanoalloys in systems of Au-Ir, Au-Rh and Au-Ir-Rh, with large bulk miscibility gaps, in one-run reactions under thermal decomposition of specially synthesised single-source precursors, namely, [AuEn2][Ir(NO2)6], [AuEn2][Ir(NO2)6] х [Rh(NO2)6]1-х and [AuEn2][Rh(NO2)6]. The precursors employed contain all desired metals 'mixed' at the atomic level, thus providing significant advantages for obtaining alloys. The observations using high-resolution transmission electron microscopy show that the nanoalloy structures are composed of well-dispersed aggregates of crystalline domains with a mean size of 5 ± 3 nm...
May 19, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28380024/gelatin-device-for-the-delivery-of-growth-factors-involved-in-endochondral-ossification
#20
Lucas A J Ahrens, Daniel Vonwil, Jon Christensen, V Prasad Shastri
Controlled release drug delivery systems are well established as oral and implantable dosage forms. However, the controlled release paradigm can also be used to present complex soluble signals responsible for cellular organization during development. Endochondral ossification (EO), the developmental process of bone formation from a cartilage matrix is controlled by several soluble signals with distinct functions that vary in structure, molecular weight and stability. This makes delivering them from a single vehicle rather challenging...
2017: PloS One
keyword
keyword
116646
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"