keyword
MENU ▼
Read by QxMD icon Read
search

hydrogen production

keyword
https://www.readbyqxmd.com/read/28549328/enhanced-photocatalytic-hydrogen-production-from-aqueous-sulfide-sulfite-solution-by-zno0-6s0-4-with-simultaneous-dye-degradation-under-visible-light-irradiation
#1
Ka Him Chu, Liqun Ye, Wei Wang, Dan Wu, Donald Ka Long Chan, Cuiping Zeng, Ho Yin Yip, Jimmy C Yu, Po Keung Wong
Photocatalytic hydrogen (H2) production was performed by visible-light-driven (VLD) ternary photocatalyst, zinc oxysulfide (ZnO0.6S0.4) in the presence of sulfide/sulfite (S2(2-)/SO3(2-)) sacrificing system, with simultaneous azo-dye Reactive Violet 5 (RV5) degradation. Enhancement in both RV5 degradation and H2 production was achieved, with the promotion of H2 production after decolorization of RV5. The effect of initial concentration of RV5 was found to be influential on the enhancement of H2 during the simultaneous processes, with a maximum of 110% increase of H2 produced...
May 20, 2017: Chemosphere
https://www.readbyqxmd.com/read/28549266/self-cascade-reaction-catalyzed-by-cuo-nanoparticle-based-dual-functional-enzyme-mimics
#2
Ai-Ling Hu, Hao-Hua Deng, Xiao-Qing Zheng, Yan-Yu Wu, Xiu-Ling Lin, Ai-Lin Liu, Xing-Hua Xia, Hua-Ping Peng, Wei Chen, Guo-Lin Hong
It is desirable but challenging to assemble various biomimetic properties into a functional catalytic cascade system. In this work, cupric oxide nanoparticles were investigated as oxidase mimics for the aerobic oxidation of cysteine to cystine with the generation of hydrogen peroxide. Coupling this property with the peroxidase-like activity of CuO nanoparticles, we constructed a self-organized cascade reaction system based on a single-component nanozyme, which includes the oxidation of cysteine to yield cystine and hydrogen peroxide and the hydrogen peroxide-mediated oxidation of terephthalic acid to produce a fluorescence change...
May 19, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28548374/continuous-synthesis-and-purification-by-coupling-a-multistep-flow-reaction-with-centrifugal-partition-chromatography
#3
Róbert Örkényi, János Éles, Ferenc Faigl, Péter Vincze, Anita Prechl, Zoltán Szakács, János Kóti, István Greiner
Continuous-flow multistep synthesis meets quasi-continuous final-product purification to produce pure products from crude reaction mixtures. In the nucleophilic aromatic substitution of 2,4-difluoronitrobenzene with morpholine followed by a heterogeneous catalytic hydrogenation, the desired monosubstituted product can be continuously separated from the by-products in a purity of over 99 % by coupling a flow reactor sequence to a multiple dual-mode (MDM) centrifugal partition chromatography (CPC) device. It has many advantages as compared to HPLC, such as higher resolution, no need for column replacement or silica to recycle, and it is absolutely free of irreversible adsorption...
May 26, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28548158/visible-light-assisted-hydrogen-generation-from-complete-decomposition-of-hydrous-hydrazine-using-rhodium-modified-tio2-photocatalysts
#4
Pawan Kumar, Anurag Kumar, Clémence Queffélec, Dietrich Gudat, Qi Wang, Suman L Jain, Rabah Boukherroub, Sabine Szunerits
Hydrogen is considered to be an ideal energy carrier, which produces only water when combined with oxygen and thus has no detrimental effect on the environment. While the catalytic decomposition of hydrous hydrazine for the production of hydrogen is well explored, little is known about its photocatalytic decomposition. The present paper describes a highly efficient photochemical methodology for the production of hydrogen through the decomposition of aqueous hydrazine using titanium dioxide nanoparticles modified with a Rh(i) coordinated catechol phosphane ligand (TiO2-Rh) as a photocatalyst under visible light irradiation...
May 26, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/28547816/three-component-aminoalkylations-yielding-dihydronaphthoxazine-based-sirtuin-inhibitors-scaffold-modification-and-exploration-of-space-for-polar-side-chains
#5
Steffen Vojacek, Katja Beese, Zayan Alhalabi, Sören Swyter, Anja Bodtke, Carola Schulzke, Manfred Jung, Wolfgang Sippl, Andreas Link
Nonpolar derivatives of heterocyclic aromatic screening hits like the non-selective sirtuin inhibitor splitomicin tend to be poorly soluble in biological fluids. Unlike sp(3) -rich natural products, flat aromatic compounds are prone to stacking and often difficult to optimize into leads with activity in cellular systems. The aim of this work was to identify anchor points for the introduction of sp(3) -rich fragments with polar functional groups into the newly discovered active (IC50  = 5 μM) but nonpolar scaffold 1,2-dihydro-3H-naphth[1,2-e][1,3]oxazine-3-thione by a molecular modeling approach...
May 26, 2017: Archiv der Pharmazie
https://www.readbyqxmd.com/read/28547569/the-effect-of-long-term-use-of-tooth-bleaching-products-on-the-human-enamel-surface
#6
Olga Polydorou, Sophia Scheitza, Mathias Spraul, Kirstin Vach, Elmar Hellwig
The aim of this in vitro study was to evaluate the long-term effect of bleaching on human enamel. Four groups of enamel specimens were prepared (n = 20): group 1: bleaching with Opalescence Boost [40% hydrogen peroxide (H2O2), 3 × 20 min/week]; group 2: control group (the specimens were stored in human saliva); group 3: beaching with Vivastyle Paint on Plus (6% H2O2, 2 × 10 min/day), and group 4: bleaching with Opalescence PF 16% [16% carbamide peroxide (CP), 6 h/day]. After each bleaching session the specimens were stored in human saliva...
May 25, 2017: Odontology
https://www.readbyqxmd.com/read/28546906/recent-progress-in-energy-driven-water-splitting
#7
REVIEW
Si Yin Tee, Khin Yin Win, Wee Siang Teo, Leng-Duei Koh, Shuhua Liu, Choon Peng Teng, Ming-Yong Han
Hydrogen is readily obtained from renewable and non-renewable resources via water splitting by using thermal, electrical, photonic and biochemical energy. The major hydrogen production is generated from thermal energy through steam reforming/gasification of fossil fuel. As the commonly used non-renewable resources will be depleted in the long run, there is great demand to utilize renewable energy resources for hydrogen production. Most of the renewable resources may be used to produce electricity for driving water splitting while challenges remain to improve cost-effectiveness...
May 2017: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
https://www.readbyqxmd.com/read/28545589/gastrointestinal-tolerance-of-low-fodmap-oral-nutrition-supplements-in-healthy-human-subjects-a-randomized-controlled-trial
#8
Jennifer Erickson, Renee Korczak, Qi Wang, Joanne Slavin
BACKGROUND: There has been increasing interest in utilizing a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) for the treatment of irritable bowel syndrome (IBS), a functional gastrointestinal disease. While studies have indicated that this diet can be effective at symptom reduction, it is a restrictive diet and patients may find it challenging to find low FODMAP products to meet their nutrient needs. The primary objective of this study was to assess the gastrointestinal (GI) tolerance of three low FODMAP oral nutrition supplements (ONS) in healthy adults...
May 25, 2017: Nutrition Journal
https://www.readbyqxmd.com/read/28545261/microbicidal-activity-of-n-chlorotaurine-in-combination-with-hydrogen-peroxide
#9
Jasmin Mustedanagic, Valdecir Farias Ximenes, Markus Nagl
N-chlorotaurine (NCT) and hydrogen peroxide are powerful endogenous antiseptics. In vivo, the reaction between hydrogen peroxide and metal ions leads to the formation of free hydroxyl radicals, which have an increased bactericidal activity. This study examined whether there is an additive antimicrobial effect of NCT combined with hydrogen peroxide. Additionally, it was tested if the additive effect is based on the formation of free radicals. We found by luminometry that, in the presence of H2O2, NCT caused a slow and long-lasting production of singlet oxygen in contrast to HOCl, where this burst occurred instantaneously...
December 2017: AMB Express
https://www.readbyqxmd.com/read/28544652/brownmillerite-type-ca2fecoo5-as-a-practicable-oxygen-evolution-reaction-catalyst
#10
Etsushi Tsuji, Teruki Motohashi, Hiroyuki Noda, Damian Kowalski, Yoshitaka Aoki, Hajime Tanida, Junji Niikura, Yukinori Koyama, Masahiro Mori, Hajime Arai, Tsutomu Ioroi, Naoko Fujiwara, Yoshiharu Uchimoto, Zempachi Ogumi, Hiroki Habazaki
Here, we report remarkable oxygen evolution reaction (OER) catalytic activity of brownmillerite (BM)-type Ca2FeCoO5. The OER activity of this oxide is comparable to or beyond those of the state-of-the-art perovskite (PV)-catalyst Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) and a precious-metal catalyst RuO2, emphasizing the importance of the characteristic BM structure with multiple coordination environments of transition metal (TM) species. Also, Ca2FeCoO5 is obviously advantageous in terms of expense/laboriousness of the material synthesis...
May 25, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28544649/activation-of-co2-by-vanadium-nitrogenase
#11
Nathaniel Sickerman, Yilin Hu, Markus Walter Ribbe
The reduction of CO2 into useful products, including hydrocarbon fuels, is an ongoing area of particular interest due to efforts to mitigate buildup of this greenhouse gas. While the industrial Fischer-Tropsch process can facilitate the hydrogenation of CO2 with H2 to form short-chain hydrocarbon products under high temperatures and pressures, a desire to perform these reactions under ambient conditions has inspired the use of biological approaches. Particularly, enzymes offer insight into how to activate and reduce CO2, but only one enzyme, nitrogenase, can perform the multielectron, multiproton reduction of CO¬2 into hydrocarbons...
May 22, 2017: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/28544221/single-atom-electrocatalysts
#12
Chengzhou Zhu, Shaofang Fu, Qiurong Shi, Dan Du, Yuehe Lin
Recent years have witnessed the increasing production of the sustainable and renewable energy. The limitations of electrochemical performances are closely associated with the search for highly efficient electrocatalysts with more rational control of size, shape, composition and structure. Specifically, the rapidly emerging studies on single-atom catalysts (SACs) have sparked new interests in electrocatalysis because of the unique properties such as high catalytic activity, selectivity and 100% atom utilization...
May 23, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28544164/rapid-production-of-high-purity-hydrogen-fuel-through-microwave-promoted-deep-catalytic-dehydrogenation-of-liquid-alkanes-with-abundant-metals
#13
Xiangyu Jie, Sergio Gonzalez-Cortes, Tiancun Xiao, Jiale Wang, Benzhen Yao, Daniel R Slocombe, Hamid A Al-Megren, Jonathan R Dilworth, John M Thomas, Peter P Edwards
Hydrogen as an energy carrier promises a sustainable energy revolution. However, one of the greatest challenges for any future hydrogen economy is the necessity for large scale hydrogen production not involving concurrent CO2 production. The high intrinsic hydrogen content of liquid-range alkane hydrocarbons (including diesel) offers a potential route to CO2 -free hydrogen production through their catalytic deep dehydrogenation. We report here a means of rapidly liberating high-purity hydrogen by microwave-promoted catalytic dehydrogenation of liquid alkanes using Fe and Ni particles supported on silicon carbide...
May 23, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28544113/the-role-of-water-in-catalyst-free-aldol-reaction-of-water-insoluble-n-methyl-2-4-thiazolidinedione-with-n-methyl-isatin-from-qm-mm-monte-carlo-simulation
#14
Jianming Zhao, Fen He, Fan Zhang, Xin Yang, Zhiyue Tian, Ying Xue
The role of water in the uncatalyzed aldol reaction of N-methyl-2,4-thiazolidinedione with N-methyl-isatin has been investigated using Monte Carlo statistical mechanics simulations utilizing the free-energy perturbation theory and the QM/MM model with PDDG/PM3 for the QM method under the "on water" and dimethyl sulfoxide (DMSO) environments. There are several conceivable orientations between thiazolidinedione and isatin in the process of C-C bond formation. However, the formation of C-C bond takes place between the re face of isatin and the si face of E-enol of the thiazolidinedione to form the preferred anti-type product, which results from enhancing hydrogen bonding interaction between water molecules and the oxygen atoms undergoing bond broken and bond formation during the reaction...
May 23, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28543938/high-throughput-assay-for-enantiomeric-excess-determination-in-1-2-and-1-3-diols-and-direct-asymmetric-reaction-screening
#15
Elena G Shcherbakova, Valentina Brega, Vincent M Lynch, Tony D James, Pavel Anzenbacher
A simple and efficient method for determination of the yield, enantiomeric/diasteriomeric excess (ee/de), and absolute configuration of crude chiral diols without the need of work-up and product isolation in a high throughput setting is described. This approach utilizes a self-assembled iminoboronate ester formed as a product by dynamic covalent self-assembly of a chiral diol with an enantiopure fluorescent amine such as tryptophan methyl ester or tryptophanol and 2-formylphenylboronic acid. The resulting diastereomeric boronates display different photophysical properties and allow for fluorescence-based ee determination of molecules containing a 1,2- or 1,3-diol moiety...
May 23, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28540960/photochemical-reactions-of-metal-complexes-in-the-solid-state
#16
Jagadese J Vittal, Hong Sheng Quah
This perspective focusses on the solid-state reactivity and structural transformation driven by photochemical methods in discrete metal complexes, organometallic compounds, metallo-macrocycles and cages. Changes in the metal-metal bond distances, racemization of chiral centres, fusion of cages, formation of coordination polymers, expected [2 + 2] and [4 + 4] cycloaddition products, unusual phenyl-olefin dimerization, and linkage isomerization of -SO2, -NO & -NO2 ligands cause the structural transformations...
May 25, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28539708/assessment-of-mexican-arnica-heterotheca-inuloides-cass-and-rosemary-rosmarinus-officinalis-extracts-on-dopamine-and-selected-biomarkers-of-oxidative-stress-in-stomach-and-brain-of-salmonella-typhimurium-infected-rats
#17
David Calderón Guzmàn, Maribel Ortiz Herrera, Norma Osnaya Brizuela, Gerardo Barragàn Mejía, Ernestina Hernàndez García, Hugo Juàrez Olguín, Armando Valenzuela Peraza, Norma Labra Ruíz, Daniel Santamaría Del Angel
BACKGROUND: The effects of some natural products on dopamine (DA) and 5-hydroxyindole acetic acid (5-HIAA) in brain of infected models are still unclear. OBJECTIVE: The purpose of this study was to measure the effect of Mexican arnica/rosemary (MAR) water extract and oseltamivir on both biogenic amines and some oxidative biomarkers in the brain and stomach of young rats under infection condition. METHODS: Female Wistar rats (weight 80 g) in the presence of MAR or absence (no-MAR) were treated as follows: group 1, buffer solution (controls); oseltamivir (100 mg/kg), group 2; culture of Salmonella typhimurium (S...
April 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28537603/stability-of-radiation-damaged-dna-after-multiple-strand-breaks
#18
Fabio Landuzzi, Pier Luca Palla, Fabrizio Cleri
Damage to the DNA backbone occurs from natural sources, and with exceedingly large density during radiotherapy, as typically used for cancer treatment. Here, we focus on the molecular-scale dynamics of the events immediately following the production of single- and double-strand breaks, since this early-stage evolution of the damage is crucial to determine the subsequent fate of the DNA fragment. While multiple cleavage of phosphodiester bonds is the first step, however the remaining hydrogen-bond and π-stacking interactions maintain a considerable DNA cohesion, and determine further defect evolution...
May 24, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28537489/hydrogen-sulfide-as-a-potential-target-in-preventing-spermatogenic-failure-and-testicular-dysfunction
#19
Jing Wang, Wan Wang, Shuangyue Li, Yi Han, Ping Zhang, Guoliang Meng, Yujiao Xiao, Liping Xie, Xin Wang, Jiahao Sha, Qi Chen, Philip K Moore, Rui Wang, Wenpei Xiang, Yong Ji
AIMS: Testis and sperm are particularly susceptible to inflammation and oxidative stress. Although Hydrogen sulfide (H2S) has been considered as an important biological signaling molecule in inflammatory and oxidative stress processes, its role in male reproductive system was poorly understood. The aim of this study was to investigate the role of H2S in the regulation of male reproductive system. RESULTS: We found that both sub-fertile and infertile patients, especially asthenospermic patients, exhibited a decreased concentration of H2S in their seminal plasma and diminished expression of H2S-generating enzyme (cystathionine β-synthase, CBS) in sperm...
May 24, 2017: Antioxidants & Redox Signaling
https://www.readbyqxmd.com/read/28537029/arsenic-accumulation-and-physiological-attributes-of-spinach-in-the-presence-of-amendments-an-implication-to-reduce-health-risk
#20
Muhammad Shahid, Marina Rafiq, Nabeel Khan Niazi, Camille Dumat, Saliha Shamshad, Sana Khalid, Irshad Bibi
The current study examined the effect of calcium (Ca) and ethylenediaminetetraacetic acid (EDTA) on arsenic (As) uptake and toxicity to spinach (Spinacia oleracea) as well as assessed the potential human health risks. Spinach seedlings were exposed to three levels of As (25, 125, and 250 μM) alone or together with three levels of EDTA (25, 125, and 250 μM) and Ca (1, 5, and 10 mM). The effect of EDTA and Ca was assessed in terms of As contents in roots and shoots, hydrogen peroxide production, chlorophyll contents, and lipid peroxidation...
May 24, 2017: Environmental Science and Pollution Research International
keyword
keyword
58627
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"