The effect of indium introduction method on the properties of Pt/In/Al2O3-Cl reforming catalyst

2021 ◽  
Vol 21 (3) ◽  
pp. 131-137
Author(s):  
V. Yu. Tregubenko ◽  
K. V. Veretelnikov ◽  
T. I. Gulyaeva ◽  
A. S. Belyi
Keyword(s):  
Selectivity Ratio ◽  
Total Acidity ◽  
Pronounced Decrease ◽  
Reforming Catalyst ◽  
Reforming Catalysts ◽  
Heptane Conversion

The effect of 0.3 wt.% indium, which was introduced at the steps of alumina peptization or impregnation, on the properties of platinumalumina reforming catalysts was studied. Doping with indium at the impregnation step produced a smaller decrease in the total acidity of the support and hence in the heptane conversion for the corresponding Pt/In/Al2O3-Cl catalyst. The most pronounced decrease in selectivity of hydrogenolysis and hydrocracking and the maximum i-C5-7 : toluene selectivity ratio were observed for this sample as compared to the undoped catalysts with indium introduction at the peptization step.

scholarly journals In situ X-ray emission and high-resolution X-ray absorption spectroscopy applied to Ni-based bimetallic dry methane reforming catalysts

Nanoscale ◽  
2020 ◽  
Vol 12 (28) ◽  
pp. 15185-15192
Author(s):  
Abbas Beheshti Askari ◽  
Mustafa al Samarai ◽  
Nozomu Hiraoka ◽  
Hirofumi Ishii ◽  
Lukas Tillmann ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Catalytic Activity ◽  
High Resolution ◽  
Absorption Spectroscopy ◽  
Methane Reforming ◽  
X Ray ◽  
Reforming Catalyst ◽  
Reforming Catalysts ◽  
X Ray Absorption

The effect of cobalt on the catalytic activity of a NiCoO dry methane reforming catalyst was investigated by in situ XES and HERFD XAS. Co is shown to hamper the reduction of the Ni in the NiCoO catalyst by modulation of its electronic structure.

Divergent beam microanalysis studies of bimetallic platinum catalysts supported on γ-AL2O3

1995 ◽  
Vol 53 ◽  
pp. 428-429
Author(s):  
JR Fryer ◽  
Z Huang ◽  
D Stirling ◽  
G. Webb
Keyword(s):  
Dead Time ◽  
Platinum Catalysts ◽  
Beam Intensity ◽  
Beam Diameter ◽  
Divergent Beam ◽  
Bimetallic Systems ◽  
Reforming Catalyst ◽  
Before And After ◽  
Individual Particles

Platinum dispersed on γ-alumina is used as a reforming catalyst to convert linear hydrocarbons to cyclic aromatic products. To improve selectivity and lifetime of the catalyst, other elements are included, and we have studied the distributions of Pt/Re, and Pt/Sn, bimetallic systems on the support both before and after use in octane reforming. Often, one or both of the components are not resolvable by HREM or microanalysis as individual particles because of small size and lack of contrast on the alumina, and divergent beam microanalysis has been used to establish the presence and relationship between the two elements.In the majority of catalysts the platinum is in the form of small panicles, some of which are large enough to be resolvable in the microscope. The ABT002B microscope with Link windowless Pentafet detector, used in this work, was able to obtain a resolvable signal from particles of 2nm diameter upwards. When the beam was concentrated on to such a particle the signal was at a maximum, and as the beam diameter was diverged - at the same total beam intensity and dead time - the signal decreased as shown in Figure 1.

Elemental Distribution in Pt-Re:Al2O3 Naphtha Reforming Catalysts

1980 ◽  
Vol 38 ◽  
pp. 200-201
Author(s):  
R. L. Freed ◽  
M. J. Kelley
Keyword(s):  
Bimetallic Catalyst ◽  
Supported Catalysts ◽  
Coke Formation ◽  
Materials Characterization ◽  
Metal Catalyst ◽  
Elemental Distribution ◽  
Exact Nature ◽  
Naphtha Reforming ◽  
Reforming Catalysts ◽  
Commercial Introduction

The commercial introduction of Pt-Re supported catalysts to replace Pt alone on Al2O3 has brought improvements to naphtha reforming. The bimetallic catalyst can be operated continuously under conditions which lead to deactivation of the single metal catalyst by coke formation. Much disagreement still exists as to the exact nature of the bimetallic catalyst at a microscopic level and how it functions in the process so successfully. The overall purpose of this study was to develop the materials characterization tools necessary to study supported catalysts. Specifically with the Pt-Re:Al2O3 catalyst, we sought to elucidate the elemental distribution on the catalyst.

The Effect of Venous Occlusion on the Sequestration of Blood Platelets

1972 ◽  
Vol 28 (03) ◽  
pp. 383-392 ◽  
Author(s):  
J Hladovec ◽  
Z Koleilat ◽  
I Přerovský
Keyword(s):  
Blood Platelets ◽  
Venous Blood ◽  
Venous Occlusion ◽  
Blood Samples ◽  
Pronounced Decrease ◽  
Platelet Counts ◽  
Human Volunteers ◽  
Opposite Change

SummaryThe venous occlusion of all four legs in rats caused a highly significant decrease of platelet counts in venous blood especially after the correction for an opposite change in haematocrit. A very pronounced decrease in platelets was observed in human volunteers after a venostasis in one arm in the blood drawn from the occluded limb just before the release of occlusion. Similar decreases were found after a venostasis of both legs in postocclusion blood samples. The decrease in blood platelets results from temporary sequestration in the occluded limbs. The decreases of platelets after a 10 min occlusion of both legs are more pronounced in patients with post thrombotic states.

Influence of melatonin on blood pressure indicators with different severity of desynchronosis

2020 ◽  
pp. 30-40
Author(s):  
M. G. Melnik
Keyword(s):  
Blood Pressure ◽  
Circadian Rhythms ◽  
Antihypertensive Drugs ◽  
Blood Pressure Monitoring ◽  
Home Monitoring ◽  
Normal Blood ◽  
Normal Blood Pressure ◽  
Pronounced Decrease ◽  
The Third ◽  
Pressure Indicators

Purpose. To study the dynamics of blood pressure (BP) indicators under the influence of exogenously administered melatonin (Melatonin-SZ, Severnaya Zvezda, Russia) with various manifestations of desynchronosis of circadian BP rhythms (arterial hypertension – AH, high normal blood pressure) to determine the scheme of their effective compensation. Material and methods. The study included 101 patients with desynchronosis of circadian rhythms of blood pressure – 52 patients with hypertension, constituting the first and second groups, and 49 individuals with high normal blood pressure, representing the third and fourth groups. Patients of the second and fourth groups received conservative therapy, patients of the first and third groups combined it with melatonin. All patients underwent measurements of office blood pressure, home monitoring of blood pressure (ABPM), electrocardiography, 24-hour blood pressure monitoring (ABPM). Results and discussion. In patients of the first and third groups, compared with the traditional treatment groups, by the end of the observation period, a significantly (p < 0.05) decrease in office systolic blood pressure (SBP) / diastolic blood pressure (DBP) was established: in the first group compared with the second – 1.11 / 1.13 times, in the third group compared to the fourth – 1.43 / 1.58 times; significantly more (p < 0.05) pronounced decrease in SBP / DBP during DMAD – by 1.08 / 1.17 and 1.58 / 1.62 times, respectively, Significantly (p < 0.05) more pronounced decrease in average daily, average daily and average nighttime SBP / DBP during ABPM – by 1.13 / 1.20, 1.11 / 1.20, 1.23 / 1.25 and 1.47 / 1.31, 1.42 / 1.19, 1.54 / 1.41 times, respectively; reliably (p < 0.05) more frequent registration of the dipper rhythm type SBP / DBP – 1.6 / 1.4 and 1.6 / 1.4 times, respectively. In addition, the dynamics of patients in the first and third groups showed a significant (p < 0.05) decrease in the mean daily and mean nighttime SBP / DBP variability (SBP in the first group by 27.3 and 41.3 %, respectively; DBP in the first group by 20.1 and 26.3 %, respectively; SBP in the third group by 13.5 and 25.2 %, respectively; DBP in the third group by 12.2 and 28.2 %, respectively). Conclusions. With various manifestations of desynchronosis of circadian rhythms of blood pressure (AH, high normal blood pressure), the prescription of melatonin (Melatonin-SZ, Severnaya Zvezda, Russia) at a dose of 3 mg per day 30–40 minutes before bedtime for a month against the background of non-drug therapy and antihypertensive drugs led to a significantly more effective decrease in blood pressure at its office measurement, DMAD, ABPM with an improvement in the circadian rhythm of blood pressure and normalization of blood pressure variability.

Performance of Ag-HZSM-5 Zeolite Catalysts in n-heptane Conversion

2017 ◽  
Vol 68 (1) ◽  
pp. 116-120
Author(s):  
Iuliean Vasile Asaftei ◽  
Neculai Catalin Lungu ◽  
Lucian Mihail Birsa ◽  
Ioan Gabriel Sandu ◽  
Laura Gabriela Sarbu ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Metal Content ◽  
Pulse Method ◽  
Acid Strength ◽  
Strength Distribution ◽  
Zeolite Catalysts ◽  
Benzene Toluene ◽  
Acid Strength Distribution ◽  
Silver Cations ◽  
Heptane Conversion

The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.

Evaluation of the Antiulcer Activity of Ethanolic Leave Extracts of Saraca indica against Ethanol, Pylorus Ligature and Indomethacin Induced Ulcer in Albino Rats

2020 ◽  
Vol 16 (8) ◽  
pp. 1191-1196
Author(s):  
Pritt Verma ◽  
Shravan K. Paswan ◽  
Vishal K. Vishwakarma ◽  
Priyanshi Saxena ◽  
Chandana V. Rao ◽  
...  
Keyword(s):  
Mucosal Injury ◽  
Gastric Volume ◽  
Gastric Ulcers ◽  
Albino Rats ◽  
Antiulcer Activity ◽  
Cellulose Solution ◽  
Total Acidity ◽  
Ulcer Index ◽  
Standard Drug ◽  
High Doses

Background: To evaluate the antiulcer activity of ethanolic leaves extract of Saraca indica against ethanol, pylorus ligature and indomethacin in albino rats. Materials and Methods: Ulcer was produced by ethanol, pylorus ligature and indomethacin in albino rats. Five groups (n=6) of rats were orally pre-treated with carboxymethyl cellulose solution, and ranitidine (80 mg/kg) respectively. In ethanol induced ulcer, the animals were treated with 200 and 400 mg/kg b.w. ethanolic leave extracts of Saraca indica in 0.3% CMC solution, 60 minutes before oral administration of absolute ethanol to produce gastric mucosal injury. In indomethacin induced ulcer, the drug was administered orally at the dose of 30 mg/kg b.w. After 7-9 hours of administration of indomethacin (30 mg/kg); the animals were sacrificed with high doses of anesthesia. In the pylorus ligature method, volume of free acidity, gastric secretion, pH and total acidity were estimated. In all three models, the ulcer index and % protection were estimated. Results: The anti ulcer activity of ethanolic leave extracts of Saraca indica in ethanol, indomethacin and pylorus ligature models is evident from the significant (P<0.001) reduction in ulcer index. In pylorus ligature model, significant (P<0.001) reduction in total acidity gastric volume and increase in pH were observed when compared with the standard drug. Conclusion: Ethanolic leave extracts of Saraca indica were found to be significantly protective against ethanol, indomethacin and pylorus ligature induced gastric ulcers in the experimental albino rats. The result obtained suggest that ethanolic leave extracts of Saraca indica possesses significant anti-ulcer activity.

scholarly journals Screening of 5- and 6-Substituted Amiloride Libraries Identifies Dual-uPA/NHE1 Active and Single Target-Selective Inhibitors

2021 ◽  
Vol 22 (6) ◽  
pp. 2999
Author(s):  
Benjamin J. Buckley ◽  
Ashna Kumar ◽  
Ashraf Aboelela ◽  
Richard S. Bujaroski ◽  
Xiuju Li ◽  
...  
Keyword(s):  
Selectivity Ratio ◽  
Dual Targeting ◽  
Sodium Hydrogen ◽  
Type Plasminogen Activator ◽  
Single Target ◽  
Urokinase Type Plasminogen Activator ◽  
Anti Cancer ◽  
Sodium Hydrogen Exchanger ◽  
A Cell ◽  
Cell Invasiveness

The K+-sparing diuretic amiloride shows off-target anti-cancer effects in multiple rodent models. These effects arise from the inhibition of two distinct cancer targets: the trypsin-like serine protease urokinase-type plasminogen activator (uPA), a cell-surface mediator of matrix degradation and tumor cell invasiveness, and the sodium-hydrogen exchanger isoform-1 (NHE1), a central regulator of transmembrane pH that supports carcinogenic progression. In this study, we co‑screened our library of 5- and 6-substituted amilorides against these two targets, aiming to identify single-target selective and dual-targeting inhibitors for use as complementary pharmacological probes. Closely related analogs substituted at the 6-position with pyrimidines were identified as dual-targeting (pyrimidine 24 uPA IC50 = 175 nM, NHE1 IC50 = 266 nM, uPA selectivity ratio = 1.5) and uPA-selective (methoxypyrimidine 26 uPA IC50 = 86 nM, NHE1 IC50 = 12,290 nM, uPA selectivity ratio = 143) inhibitors, while high NHE1 potency and selectivity was seen with 5-morpholino (29 NHE1 IC50 = 129 nM, uPA IC50 = 10,949 nM; NHE1 selectivity ratio = 85) and 5-(1,4-oxazepine) (30 NHE1 IC50 = 85 nM, uPA IC50 = 5,715 nM; NHE1 selectivity ratio = 67) analogs. Together, these amilorides comprise a new toolkit of chemotype-matched, non-cytotoxic probes for dissecting the pharmacological effects of selective uPA and NHE1 inhibition versus dual-uPA/NHE1 inhibition.

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