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Membranes ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 95
Author(s):  
Muhammad Imran Khan ◽  
Abdallah Shanableh ◽  
Majeda Khraisheh ◽  
Fares AlMomani

Diffusion dialysis (DD) is an anion exchange membrane-based functional separation process used for acid recovery. TMA (trimethylamine) and BPPO (brominated poly (2,6-dimethyl-1,4-phenylene oxide) were utilized in this manuscript to formulate AEMs (anion exchange membranes) for DD (diffusion dialysis) using the phase-inversion technique. FTIR (Fourier transfer infrared) analysis, proton NMR spectroscopy, morphology, IEC (ion exchange capacity), LER (linear expansion ratio), CR (fixed group concentration), WR (water uptake/adsorption), water contact angle, chemical, and thermal stability, were all used to evaluate the prepared membranes. The effect of TMA content within the membrane matrix on acid recovery was also briefly discussed. It was reported that porous AEMs have a WR of 149.6% to 233.8%, IEC (ion exchange capacity) of 0.71 to 1.43 mmol/g, CR (fixed group concentration) that ranged from 0.0046 mol/L to 0.0056 mol/L, LER of 3.88% to 9.23%, and a water contact angle of 33.10° to 78.58°. The UH (acid dialysis coefficients) for designed porous membranes were found to be 0.0043 to 0.012 m/h, with separation factors (S) ranging from 13.14 to 32.87 at the temperature of 25 °C. These observations are comparable to those found in the DF-120B commercial membrane with UH of 0.004 m/h and S of 24.3 m/h at the same temperature (25 °C). This porous membranes proposed in this paper are excellent choices for acid recovery through the diffusion dialysis process.


2022 ◽  
Vol 23 (2) ◽  
pp. 791
Author(s):  
Branka Šošić-Jurjević ◽  
Svetlana Trifunović ◽  
Jasmina Živanović ◽  
Vladimir Ajdžanović ◽  
Marko Miler ◽  
...  

Vitamin D plays an essential role in prevention and treatment of osteoporosis. Thyroid hormones, in addition to vitamin D, significantly contribute to regulation of bone remodeling cycle and health. There is currently no data about a possible connection between vitamin D treatment and the thyroid in the context of osteoporosis. Middle-aged Wistar rats were divided into: sham operated (SO), orchidectomized (Orx), and cholecalciferol-treated orchidectomized (Orx + Vit. D3; 5 µg/kg b.m./day during three weeks) groups (n = 6/group). Concentration of 25(OH)D in serum of the Orx + Vit. D3 group increased 4 and 3.2 times (p < 0.0001) respectively, compared to Orx and SO group. T4, TSH, and calcitonin in serum remained unaltered. Vit. D3 treatment induced changes in thyroid functional morphology that indicate increased utilization of stored colloid and release of thyroid hormones in comparison with hormone synthesis, to maintain hormonal balance. Increased expression of nuclear VDR (p < 0.05) points to direct, TSH independent action of Vit. D on thyrocytes. Strong CYP24A1 immunostaining in C cells suggests its prominent expression in response to Vit. D in this cell subpopulation in orchidectomized rat model of osteoporosis. The indirect effect of Vit. D on bone, through fine regulation of thyroid function, is small.


Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2721
Author(s):  
Amadeja Koler ◽  
Mitja Kolar ◽  
Karel Jeřábek ◽  
Peter Krajnc

With the aim to study the influence of monomer ratio in poly(high internal phase emulsions) (polyHIPEs) on the polymer network architecture and morphology of poly(vinylbenzyl chloride-co-divinylbenzene-co-styrene) after hypercrosslinking via the internal Friedel–Crafts process, polyHIPEs with 80% overall porosity were prepared at three different initial crosslinking degrees, namely 2, 5, and 10 mol.%. All had typical interconnected cellular morphology, which was not affected by the hypercrosslinking process. Nitrogen adsorption and desorption experiments with BET and t-plot modelling were used for the evaluation of the newly introduced nanoporosity and in combination with elemental analysis for the evaluation of the extent of the hypercrosslinking. It was found that, for all three initial crosslinking degrees, the minimum amount of functional monomer, 4-vinylbenzyl chloride, was approximately 30 mol.%. Hypercrosslinking of polymers with lower concentrations of functional monomer did not result in induction of nanoporosity while the initial crosslinking degree had a much lower impact on the formation of nanoporosity.


2021 ◽  
Vol 18 (3) ◽  
pp. 339-348
Author(s):  
Serena Hussain

This paper explores the migration within as well as migration to Birmingham of Muslims, Hindus and Sikhs. It provides analysis and reflection on the relationship between migration, faith group concentration and deprivation. The findings demonstrate how Muslim, Hindu and Sikh migration trends differ for specific wards characterised by contrasting levels of both socio-economic disadvantage and faith group clustering. Hindus are shown to migrate to more affluent areas, however this does not necessarily translate to moving away from wards where there are clusters of the same faith group, as discussion on Hall Green illustrates. Muslims, on the other hand, displayed a greater propensity to move away from wards with high concentrations of the same faith group, yet this did not also result in moving to more affluent wards.


2021 ◽  
Vol 63 (8) ◽  
pp. 1132
Author(s):  
Н.А. Теплякова ◽  
М.В. Смирнов ◽  
Н.В. Сидоров ◽  
М.Н. Палатников

The features of defect structure and their influence on the properties of LiNbO3:Zn crystals, doped in a wide concentration range, including two concentration thresholds (at ~ 3.0 and ~ 6.8 mol. % ZnO in the melt), were studied by absorption IR spectroscopy in the region of OH--group valence vibrations, photoluminescence in the visible region of the spectrum, and photoinduced light scattering. In LiNbO3:Zn(0.004-2.01 mol. % ZnO) crystals the increase of zinc concentration led to increasing in the OH--group concentration and decreasing the luminescence intensity of luminescence centers associated with NbLi defects. Apparently, the latter was connected with the formation of small energy levels near the bottom of the conduction band as the zinc atoms displaced niobium atoms from the lithium positions in the ideal structure and the NbLi defect concentration decreased, respectively. In highly doped LiNbO3:Zn crystals (4.46-6.5 mol. % ZnO) and in the LiNbO3stoich(6.0 wt. % K2O) crystal there were lower OH--group concentration, the increase of band gap by 0.3-0.4 eV, and the increase of luminescence intensity in the green region of the spectrum due to the formation of new recombination channels compared to weakly doped crystals. In addition, in such crystals, the increase of proton conductivity was observed due to increasing in the concentration of interstitial hydrogen H+ and, as a result, the formation of many small acceptor levels near the valence band.


2020 ◽  
Vol 2 (6) ◽  
pp. 2414-2425 ◽  
Author(s):  
Joseph M. Dennis ◽  
Tyler R. Long ◽  
Ajay Krishnamurthy ◽  
Ngon T. Tran ◽  
Brendan A. Patterson ◽  
...  

2020 ◽  
Vol 38 (3) ◽  
pp. 033005 ◽  
Author(s):  
Askar A. Rezvanov ◽  
Andrey V. Miakonkikh ◽  
Dmitry S. Seregin ◽  
Alexey S. Vishnevskiy ◽  
Konstantin A. Vorotilov ◽  
...  

2020 ◽  
Vol 18 (3) ◽  
pp. 770-787
Author(s):  
Ayal Feinberg

Over the last two decades alone, the United States has suffered well over ten thousand religion-motivated hate crimes. While racism and religion-motivated prejudice have received considerable attention following the “Unite the Right” rally in Charlottesville that resulted in deadly violence, there is little systematic scholarship evaluating where and when incidents targeting ethnoreligious minorities by non-state actors are likely to occur. Utilizing the FBI’s reported anti-Semitic hate crime data from 2001–2014, my main theoretical and empirical exercise is to determine which factors best explain where and when American ethnoreligious groups are likely to be targeted. I propose that there are four essential mechanisms necessary to explain variation in minority targeting: “opportunity” (target group concentration), “distinguishability” (target group visibility), “stimuli” (events increasing target group salience) and “organization” (hate group quantity). My models show that variables falling within each of these theoretical concepts significantly explain variation in anti-Semitic incidents in the United States. Of particular importance for scholars and practitioners alike, Israeli military operations and the number of active hate groups within a state play a major role in explaining anti-Semitic incident variation.


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