Reducing the high hydrogen binding strength of vanadium carbide MXene with atomic Pt confinement for high activity toward HER

A technique that made it possible for the first time to achieve fivefold symmetry in palladium nanocrystallites grown on the surface of a Pd-Cu film has been developed. Pd-40%Cu membrane modification with pentatwinned nanocrystallites with high-index facets made it possible to achieve ultra-high hydrogen permeability up to 10.1 mmol s-1 m-2 at 100 °C. Such permeability, comparable in value to high-temperature analogs, is anomalous, since the predicted values should be more than 2 times lower than those obtained. This result is due to the acceleration of surface dissociative adsorption and recombinative desorption as a result of the pentatwinned particles ultra-high activity in reactions involving hydrogen, which is confirmed by the data on the selectivity of the developed membranes.

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Modifying hydrogen binding strength of graphene

Surface Science ◽

10.1016/j.susc.2018.08.009 ◽

2019 ◽

Vol 679 ◽

pp. 24-30 ◽

Cited By ~ 1

Author(s):

Mohammad Panahi ◽

Navid Solati ◽

Sarp Kaya

Keyword(s):

Hydrogen Binding ◽

Binding Strength

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Laser irradiation in water for the novel, scalable synthesis of black TiO x photocatalyst for environmental remediation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.8.21 ◽

2017 ◽

Vol 8 ◽

pp. 196-202 ◽

Cited By ~ 8

Author(s):

Massimo Zimbone ◽

Giuseppe Cacciato ◽

Mohamed Boutinguiza ◽

Vittorio Privitera ◽

Maria Grazia Grimaldi

Keyword(s):

High Activity ◽

Laser Irradiation ◽

Environmental Remediation ◽

Pt Nanoparticles ◽

High Repetition Rate ◽

Solar Irradiation ◽

Rear Side ◽

Visible Radiation ◽

High Hydrogen ◽

Scalable Synthesis

Since 1970, TiO2 photocatalysis has been considered a possible alternative for sustainable water treatment. This is due to its material stability, abundance, nontoxicity and high activity. Unfortunately, its wide band gap (≈3.2 eV) in the UV portion of the spectrum makes it inefficient under solar illumination. Recently, so-called “black TiO2” has been proposed as a candidate to overcome this issue. However, typical synthesis routes require high hydrogen pressure and long annealing treatments. In this work, we present an industrially scalable synthesis of TiO2-based material based on laser irradiation. The resulting black TiO x shows a high activity and adsorbs visible radiation, overcoming the main concerns related to the use of TiO2 under solar irradiation. We employed a commercial high repetition rate green laser in order to synthesize a black TiO x layer and we demonstrate the scalability of the present methodology. The photocatalyst is composed of a nanostructured titanate film (TiO x ) synthetized on a titanium foil, directly back-contacted to a layer of Pt nanoparticles (PtNps) deposited on the rear side of the same foil. The result is a monolithic photochemical diode with a stacked, layered structure (TiO x /Ti/PtNps). The resulting high photo-efficiency is ascribed to both the scavenging of electrons by Pt nanoparticles and the presence of trap surface states for holes in an amorphous hydrogenated TiO x layer.

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New hydrogen-bonding organocatalysts: Chiral cyclophosphazanes and phosphorus amides as catalysts for asymmetric Michael additions

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.18 ◽

2014 ◽

Vol 10 ◽

pp. 224-236 ◽

Cited By ~ 20

Author(s):

Helge Klare ◽

Jörg M Neudörfl ◽

Bernd Goldfuss

Keyword(s):

Hydrogen Bonding ◽

Catalytic Activity ◽

High Activity ◽

Michael Addition ◽

Bond Activation ◽

High Catalytic Activity ◽

Open Chain ◽

High Hydrogen ◽

Michael Additions ◽

Asymmetric Michael Addition

Ten novel hydrogen-bonding catalysts based on open-chain PV-amides of BINOL and chinchona alkaloids as well as three catalysts based on rigid cis-PV-cyclodiphosphazane amides of N 1,N 1-dimethylcyclohexane-1,2-diamine have been developed. Employed in the asymmetric Michael addition of 2-hydroxynaphthoquinone to β-nitrostyrene, the open-chain 9-epi-aminochinchona-based phosphorus amides show a high catalytic activity with almost quantitative yields of up to 98% and enantiomeric excesses of up to 51%. The cyclodiphosphazane catalysts show the same high activity and give improved enantiomeric excesses of up to 75%, thus representing the first successful application of a cyclodiphosphazane in enantioselective organocatalysis. DFT computations reveal high hydrogen-bonding strengths of cyclodiphosphazane PV-amides compared to urea-based catalysts. Experimental results and computations on the enantiodetermining step with cis-cyclodiphosphazane 14a suggest a strong bidentate H-bond activation of the nitrostyrene substrate by the catalyst.

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Microscopic versus process parameters in heavy-oil upgrading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012223x ◽

1992 ◽

Vol 50 (1) ◽

pp. 366-367

Author(s):

V.A. Munoz ◽

R.J. Mikula ◽

C. Payette ◽

W.W. Lam

Keyword(s):

Molecular Weight ◽

Liquid Fuels ◽

Chemical Components ◽

Heavy Oils ◽

Synthetic Fuels ◽

High Hydrogen ◽

Optical Texture ◽

Polar Groups ◽

Anisotropic Character ◽

Planar Molecules

The transformation of high molecular weight components present in heavy oils into useable liquid fuels requires their decomposition by means of a variety of processes. The low molecular weight species produced recombine under controlled conditions to generate synthetic fuels. However, an important fraction undergo further recombination into higher molecular weight components, leading to the formation of coke. The optical texture of the coke can be related to its originating components. Those with high sulfur and oxygen content tend to produce cokes with small optical texture or fine mosaic, whereas compounds with relatively high hydrogen content are likely to produce large optical texture or domains. In addition, the structure of the parent chemical components, planar or nonplanar, determines the isotropic or anisotropic character of the coke. Planar molecules have a tendency to align in an approximately parallel arrangement to initiate the formation of the nematic mesophase leading to the formation of anisotropic coke. Nonplanar highly alkylated compounds and/or those rich in polar groups form isotropic coke. The aliphatic branches produce steric hindrance to alignment, whereas the polar groups participate in cross-linking reactions.

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The accumulation of solutes and water binding strength in durum wheat

Physiologia Plantarum ◽

10.1034/j.1399-3054.1994.900413.x ◽

1994 ◽

Vol 90 (4) ◽

pp. 715-721 ◽

Cited By ~ 1

Author(s):

A. Rascio ◽

C. Platani ◽

G. Scalfati ◽

A. Tonti ◽

N. Di Fonzo

Keyword(s):

Durum Wheat ◽

Water Binding ◽

Binding Strength

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High-activity samarium-153-EDTMP therapy followed by autologous peripheral blood stem cell support in unresectable osteosarcoma

Nuklearmedizin ◽

10.1055/s-0038-1625284 ◽

2001 ◽

Vol 40 (06) ◽

pp. 215-220 ◽

Cited By ~ 33

Author(s):

S. Bielack ◽

S. Flege ◽

J. Eckardt ◽

J. Sciuk ◽

H. Jürgens ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

High Activity ◽

Peripheral Blood ◽

Peripheral Blood Stem Cell ◽

Blood Stem Cell ◽

High Dose ◽

External Radiotherapy ◽

Primary Tumor Site ◽

Hematopoietic Stem

Summary Purpose: Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. These patients may benefit from therapy with radiolabeled phosphonates. Patients and Methods: Six patients (three male, three female; seven to 41 years) with unresectable primary osteosarcoma (n = 3) or unresectable recurrent sites of osteosarcomas (n = 3) were treated with high-activity of Sm-153-EDTMP (150 MBq/kg BW). In all patients autologous peripheral blood stem cells had been collected before Sm-153-EDTMP therapy. Results: No immediate adverse reactions were observed in the patients. In one patient bone pain increased during the first 48 hrs after therapy. Three patients received pain relief. Autologous peripheral blood stem cell reinfusion was performed on day +12 to +27 in all patients to overcome potentially irreversible damage to the hematopoietic stem cells. In three patient external radiotherapy of the primary tumor site was performed after Sm-153-EDTMP therapy and in two of them polychemotherapy was continued. Thirty-six months later one of these patients is still free of progression. Two further patients are still alive. However, they have developed new metastases. The three patients who had no accompanying external radiotherapy, all died of disease progression five to 20 months after therapy. Conclusion: These preliminary results show that high-dose Sm-153-EDTMP therapy is feasible and warrants further evaluation of efficacy. The combination with external radiation and polychemotherapy seems to be most promising. Although osteosarcoma is believed to be relatively radioresistant, the total focal dose achieved may delay local progression or even achieve permanent local tumor control in patients with surgically inaccessible primary or relapsing tumors.

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Gastric Fibrinolysis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651400 ◽

1975 ◽

Vol 34 (02) ◽

pp. 409-418 ◽

Cited By ~ 9

Author(s):

I. M Nilsson ◽

S.-E Bergentz ◽

U Hedner ◽

K Kullenberg

Keyword(s):

Gastric Ulcer ◽

Gastric Juice ◽

High Activity ◽

Fibrinolytic Activity ◽

Duodenal Juice ◽

Bleeding Tendency ◽

Local Fibrinolysis ◽

Heated Plates

SummaryGastric juice from 15 normals, 20 patients with gastric ulcer and 4 patients with erosive haemorrhagic gastroduodenitis was investigated in respect of its activity on unheated and heated fibrin plates and its content of FDP and plasminogen or plasmin with immunochemical methods. Gastric juice from normals showed no activity on unheated and heated fibrin plates, and no FDP or plasminogen could be demonstrated. In the patients with gastric ulcer the gastric juice showed little or no fibrinolytic activity on fibrin plates except in 2, who had regurgitation of duodenal juice and neutral pH of the juice. These patients had equally high activity on heated as on unheated plates and no plasmin could be demonstrated. It was shown that this activity was not due to fibrinolysis, but to non-specific proteolytic activity (probably trypsin). The patients with erosive haemorrhagic gastroduodenitis exhibited quite a different picture. The gastric juice from these patients showed extremely high activity on fibrin plates, the activity was higher on unheated than on heated plates. The activity was inhibited in vitro by addition of EACA and in vivo after administration of AMCA. The occurrence of plasmin could be demonstrated directly immunologically in the gastric juice. By comparison of plasmin and trypsin in various assays it could further be proved that the gastric juice in these cases contained plasminogen activator and plasmin. The patients with erosive haemorrhagic gastroduodenitis showed no increase in fibrinolysis in the blood, but low values for plasminogen and α2M, and the serum contained FDP. These findings in the blood and gastric juice were interpreted as signs of local fibrinolysis in the stomach and duodenum. There is reason to assume that this gastric fibrinolysis contributes substantially to the bleeding tendency. The effect of administration of AMCA on fibrinolytic activity and the haemorrhage lends support to the assumption of such a mechanism.

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