Gas-Particle Partitioning and SOA Yields of Organonitrate Products from NO3-Initiated Oxidation of Isoprene under Varied Chemical Regimes

The effect of estrogens and androgens on hepatic glycolithocholate sulfotransferase activity was studied in male rats. Significant increases in specific activity were noted following treatment of rats for 21 days with 17 beta-estradiol, 17 alpha-ethynylestradiol, and the nonsteroidal estrogen agonists nafoxidine, tamoxifen, and diethylstilbestrol. Similar treatment of male rats with 5 alpha-dihydrotestosterone, hydrocortisone, norethindrone, and prolactin did not affect activity. To further assess the effect of androgens, male rats were castrated. Glycolithocholate sulfotransferase activity increased fivefold by 14 days after castration. Treatment of castrated rats with 5 alpha-dihydrotestosterone prevented the increase and maintained activity at the level of sham-operated animals. Castrated animals exhibited an additional increment in activity following treatment with 17 alpha-ethynylestradiol: specific activity in these animals rose to levels comparable with those measured in untreated female rats. These data suggest endogenous androgens maximally suppress hepatic glycolithocholate sulfotransferase activity in male rats. The data also indicate that activity is stimulated by estrogenic compounds of varied chemical structure and that stimulation is not solely due to suppression of androgen release by the testes as a consequence of estrogen treatment.

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The Influence of a Polymer Powder on the Properties of a Cold-Recycled Mixture with Foamed Bitumen

Materials ◽

10.3390/ma12244244 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4244 ◽

Cited By ~ 2

Author(s):

Przemysław Buczyński ◽

Marek Iwański

Keyword(s):

Physical And Mechanical Properties ◽

Void Content ◽

Reclaimed Asphalt Pavement ◽

Reclaimed Asphalt ◽

Polymer Powder ◽

Varied Chemical ◽

Foamed Bitumen ◽

Powder Type ◽

Air Void ◽

Reference Mixture

The paper investigates the influence of redispersible polymer powder (RPP) on the physical and mechanical properties of a cold-recycled mixture with foamed bitumen (CRM-FB). Four types of RPP with a varied chemical base were used: VA-VeoVA, VA-VeoVa-Ac, EVA and VA/VV/E/Ac. The polymer powder-modified cold recycled mixture with foamed bitumen, (P)CRM-FB, was composed of 45.8% reclaimed asphalt pavement (RAP), 45.8% natural aggregate (VA), 3.0% Portland cement CEM I 42,5R, 3.0% foamed bitumen 50/70 and 3.0% RPP, all dosed by weight. The reference mixture, (R)CRM-FB, served as a reference point for comparison. It was found that RPP improved the workability of the CRM-FB mixture. This results in a reduced number of compaction cycles and lower energy needed to obtain the air void content as in the reference mixture. In addition, the RPP modifier markedly increased the CRM-FB mixture cohesion (ITSDRY) and strength, by approximately 40–70%, depending on the RPP used. These findings are particularly important for CRM-FB mixtures designed for road bases. The present investigations confirmed the improvement of the CRM-FB mixture parameters after the modification with RPP, regardless of the powder type used.

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Effect of Heat Treatment on Microstructure and Mechanical Properties of 15-5 pH Stainless Steel for Fastener Applications

Diffusion Foundations ◽

10.4028/www.scientific.net/df.22.118 ◽

2019 ◽

Vol 22 ◽

pp. 118-139

Author(s):

Faisal Aldhabib ◽

Xiao Dong Sun ◽

Abdullah Alsumait ◽

Fahad Alzubi ◽

Elias Ashe ◽

...

Keyword(s):

Heat Treatment ◽

Stainless Steel ◽

High Performance ◽

Heat Treatments ◽

Systematic Evaluation ◽

Chemical Compositions ◽

Heating Rates ◽

Sem Images ◽

Varied Chemical ◽

Mechanical And Microstructural Properties

15-5PH stainless steel is widely used in the aerospace industry, from precision fuse pins to forged products, due to its various high-performance properties. However, there is little systematic evaluation of heat treatment responses, especially at ultra-high temperatures above 650°C (1200°F). The objective of this work was to evaluate the mechanical and microstructural properties of 15-5 PH stainless steel at various heat treatments. Multiple heat treatment parameters were tested. The samples tested had varied chemical compositions because they were from different vendors. The experimental work included multiple aging temperatures, time, heating rates, and the effects of multiple aging treatments. A total of 38 different heat treatments were conducted on these specimens. There was a linear correlation between hardness and ultimate and yield strength. Optical microscopy showed martensitic structures with very fine grains in all the tested samples. Scanning Electron Microscope (SEM) images showed ductile fracture in all the samples.

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Tunable Electronic Transport Properties of 2D Layered Double Hydroxide Crystalline Microsheets with Varied Chemical Compositions

Small ◽

10.1002/smll.201601354 ◽

2016 ◽

Vol 12 (33) ◽

pp. 4471-4476 ◽

Cited By ~ 11

Author(s):

Yibing Zhao ◽

Hai Hu ◽

Xiaoxia Yang ◽

Dongpeng Yan ◽

Qing Dai

Keyword(s):

Transport Properties ◽

Layered Double Hydroxide ◽

Electronic Transport ◽

Chemical Compositions ◽

Electronic Transport Properties ◽

Varied Chemical ◽

Double Hydroxide

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Study on Treatment of Printing and Dyeing Wastewater by Magnetic Seed Coagulation - High Gradient Magnetic Separation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.2689 ◽

2011 ◽

Vol 71-78 ◽

pp. 2689-2694 ◽

Cited By ~ 1

Author(s):

Wen Song Chen ◽

Hua Shi Lin ◽

Shuo Feng Zhang

Keyword(s):

Magnetic Separation ◽

Magnetic Particle ◽

Removal Rate ◽

Steel Wire ◽

Dyeing Wastewater ◽

Technological Parameters ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Printing And Dyeing Wastewater ◽

Varied Chemical

Treatment of printing and dyeing wastewater by the device of high gradient magnetic separation (HGMS) developed by author was tested. The results showed that printing and dyeing wastewater contained varied chemical composition and whose initial concentration of chromaticity and COD were 800 and 565mg/L respectively can be well cleaned by Fenton oxidation—magnetic seed coagulation—HGMS. The removal rate of chromaticity and COD was up to 92.6% and 79.5% respectively. The effluent can meet the national drainage criterion. The optimum technological parameters are as follows: pH=6, [FeSO4·7H2O]=250mg/L, [H2O2]=1.3ml/L, [PAM]=0.75 mg/L, dose of magnetic particle W=150mg/L,current intensity I=8A, current velocity U=2.420L/min, packing density of stainless steel wire R=1.00%-1.43%. Recovery rate of magnetic particle was up to 90% by regenerated technique of chemistry in combination with physics.

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Antioxidant Capacity and Polyphenolic Compounds of Blackberries Produced in Different Climates

HortScience ◽

10.21273/hortsci14377-19 ◽

2019 ◽

Vol 54 (12) ◽

pp. 2209-2213 ◽

Cited By ~ 1

Author(s):

Camila P. Croge ◽

Francine L. Cuquel ◽

Paula T.M. Pintro ◽

Luiz A. Biasi ◽

Claudine M. De Bona

Keyword(s):

Antioxidant Activity ◽

Antioxidant Capacity ◽

Bioactive Compounds ◽

Abiotic Factors ◽

Ascorbic Acid Content ◽

Climatic Conditions ◽

Total Polyphenols ◽

Chemical Structures ◽

Varied Chemical ◽

Monomeric Anthocyanins

Antioxidants are compounds with varied chemical structures that are affected by biotic and abiotic factors. The objective of this study was to characterize and compare bioactive compounds and the antioxidant capacity of fruit from four blackberry cultivars produced under different climatic conditions. Ascorbic acid content, total polyphenols, flavonoids, monomeric anthocyanins and antioxidant activity of the fruit were evaluated, and high levels of bioactive compounds as well as antioxidant activity were observed regardless of the cultivar or growing location. The results showed that bioactive production is affected by the cultivar and environment. Furthermore, the antioxidant potential of the blackberry fruit depends on the total phenolics and anthocyanin.

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MORPHOLOGICAL AND CHEMICAL CHARACTERISTICS OF VARIOUS PUMMELO (Citrus maxima (Burm.) Merr.) ACCESSIONS FROM MAGETAN REGENCY

JURNAL AGRONIDA ◽

10.30997/jag.v3i2.1043 ◽

2018 ◽

Vol 3 (2) ◽

Author(s):

Arifah Rahayu ◽

Wini Nahraeni ◽

Nur Rochman ◽

Rizki Yora Ardiansyah

Keyword(s):

Vitamin C ◽

Titratable Acidity ◽

Soluble Solids ◽

Chemical Characteristics ◽

Core Width ◽

Total Titratable Acidity ◽

Citrus Maxima ◽

Varied Chemical ◽

Biology Laboratory ◽

Edible Parts

Magetan Regency was the production centre of pummelo that have many accessions with various morphological and chemical characteristics, but only a few of them were identificated. This study was aimed at identifying morphological and chemical characteristics of pummelo fruits in Magetan Regency. The study was conducted in the Biology Laboratory of Djuanda University, Bogor from May to July 2015. Results showed with regard to their morphological characteristic, pomelo plants in this region were found to have spheroid and spheroid-pyriform fruits and the weight of their fruit parts, fruit core width, mesocarp thickness, fruit circle before peeling, fruit circle after peeling, number of fruit segments, number of developed seeds, and edible parts of the fruit were varied. Chemical characteristics were also found to be varied with vitamin C content of 29.80−44.66 mg/100g, total soluble solids (TSS) content of 8.10−9.72°Brix, total titratable acidity (TAA) of 0.31−0.53 g/100 ml, and TSS/ TAA ratio of 17.69−28.58. Key words: production centre of pummelo, spheroid, vitamin C, TSS

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Deployment and Comparison of a Low-Cost High-Sensitivity Concentration Meters Using Micro-Optical Resonators

Proceedings ◽

10.3390/iecb2020-07091 ◽

2020 ◽

Vol 60 (1) ◽

pp. 53

Author(s):

Amir R. Ali ◽

Maram Wael ◽

Reem Amr Assal

Keyword(s):

Chemical Composition ◽

Morphological Changes ◽

Low Cost ◽

High Sensitivity ◽

Single Mode ◽

Optical Resonators ◽

Optical Resonator ◽

Single Mode Laser ◽

Varied Chemical ◽

Very High

Micro-optical resonators have been introduced as sensors in many applications for a wide number of variable types of stimuli due to their very high resolution, high sensitivity, and high-quality factor. In this paper, a novel micro-optical sensor was designed and tested as a concentration meter for chemical composition of a solution. The micro-optical resonator used is based on whispering gallery mode (WGM). This phenomenon appears when a tapered, single-mode laser carrying micro-optical fiber is evanescently coupled with a polymeric or silica micro-optical resonator. The presented sensor shows the change in concentration by experiencing a change in its morphology due to the varied viscosity of its environment. The variation of concentrations or fluid contents results in a change between the radii of the micro-optical resonator. With varied chemical composition and concentration in the tested sample varied infinitesimally small morphological changes are detected. The change in the resonators shape is read as a WGM shift in the resonance transmission spectrum, which is interpreted using a technique called cross-correlation, which compares the output across time to display the shift, which is later translated into distinct concentration levels. The proposed, exceptionally low-cost sensors were able to detect change at very high resolutions allowing better sensitivity along with wider range of variation. Experimental work for detection of ranges of concentrations of variable type of contaminants is presented.

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Towards Identification of Zircon Populations in Permo-Carboniferous Rhyolites of Central Europe: Insight from Automated SEM-Mineral Liberation Analyses

Minerals ◽

10.3390/min10040308 ◽

2020 ◽

Vol 10 (4) ◽

pp. 308

Author(s):

Arkadiusz Przybyło ◽

Anna Pietranik ◽

Bernhard Schulz ◽

Christoph Breitkreuz

Keyword(s):

Central Europe ◽

Detailed Examination ◽

Quantitative Information ◽

Chemical Compositions ◽

Sem Images ◽

Thin Sections ◽

Varied Chemical ◽

Different Populations ◽

Automated Scanning ◽

Sem Analyses

Zircon is a main mineral used for dating rhyolitic magmas as well as reconstructing their differentiation. It is common that different populations of zircon grains occur in a single rhyolitic sample. The presence of both autocrystic and antecrystic zircon grains is reflected in their strongly varied chemical compositions and slight spread of ages. However, postmagmatic processes may induce lead loss, which is also recorded as a spread of zircon ages. Therefore, new approaches to identify different zircon populations in rhyolitic rocks are needed. In this study, we suggest that detailed examination of zircon positions in the thin sections of rhyolitic rocks provides valuable information on zircon sources that can be used to identify autocrystic and antecrystic zircon populations. Automated Scanning Electron Microscope (SEM) analyses are of great applicability in determining this, as they return both qualitative and quantitative information and allow for quick comparisons between different rhyolite localities. Five localities of Permo-Carboniferous rhyolites related to post-Variscan extension in Central Europe (Organy, Bieberstein, Halle, Chemnitz, Krucze) were analyzed by automated SEM (MLA-SEM). The samples covered a range of Zr whole rock contents and displayed both crystalline and glassy groundmass. Surprisingly, each locality seemed to have its own special zircon fingerprint. Based on comparisons of whole rocks, modal composition and SEM images Chemnitz ignimbrite was interpreted as containing mostly (or fully) antecrystic zircon, whereas the Bieberstein dyke was shown to possibly contain both types, with the antecrystic zircon being associated with disturbed cumulates. On the other hand, Organy was probably dominated by autocrystic zircon, and Krucze contained dismembered, subhedral zircon in its matrix, whereas Halle zircon was located partly in late veins, filling cracks in laccolith. Both localities may, therefore, contain zircon populations that represent later stages than the crystallization of the main rhyolitic body.

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Some Recent Developments in the Characterization of Estuarine Particulates

Water Science & Technology ◽

10.2166/wst.1986.0183 ◽

1986 ◽

Vol 18 (4-5) ◽

pp. 83-92 ◽

Cited By ~ 11

Author(s):

J. M. Martin ◽

J. M. Mouchel ◽

P. Nirel

Keyword(s):

Exchange Capacity ◽

Small Range ◽

Coastal Zones ◽

Amorphous Oxides ◽

Al Content ◽

Physical Environments ◽

Recent Developments ◽

Varied Chemical ◽

Cationic Exchange ◽

Highly Correlated

Estuaries and coastal zones are characterised by very varied chemical and physical environments. As a result, heterogenous reactions predominate between dissolved and mineral phases, and with the biota. These reactions primarily affect elements and compounds located at the particulate surface. Thus the determination of surface properties of particles is an important key to understanding interactions of trace elements and organic compounds between particulate and dissolved phases in estuarine and coastal systems. Specific surface area (SSA), cationic exchange capacity (CEC) and heat of immersion (∆H) have been measured on native untreated suspended sediment and after oxidation with 15% H2O2. SSA and ∆H have also been measured on samples Leached with NaOH and Na-dithionite in order to remove amorphous aluminosilicates. Results indicated that SSA is controlled by amorphous oxides and is related to the Al content of samples and their granulometry, suggesting an almost uniform coating of the detrital core by amorphous oxides. On the other hand, CEC and ∆H, which appear to be highly correlated, are controlled by both organic matter and amorphous oxides. Studies on electrophoretic mobility have provided additional data on the excess of charge at the interface between suspended matter and electrolytic medium. Particles in suspension in fresh, sea, and estuarine waters appear ubiquitously to exhibit a small range of negative surface charge. This uniformity is attributed to the presence of organic surface coatings on the particles (Loder and Liss, 1985). Finally, the significance of organic and oxide coatings as carriers of trace metal pollutants is discussed. It is shown that their importance in terms of flux is usually Low despite their major role in controlling solid-liquid interactions.

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