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1. Spin diffusion transfer difference (SDTD) NMR: An advanced method for the characterisation of water structuration within particle networks

Author:
Gabrielli, Valeria; Kuraite, Agne; da Silva, Marcelo Alves; Edler, Karen J.; Angulo, Jesús; Nepravishta, Ridvan; Muñoz–García, Juan C.; Khimyak, Yaroslav Z.
Source:
Journal of colloid and interface science 2021 v.594 pp. 217-227
ISSN:
0021-9797
Subject:
equations,   etc   ; solvents; starch;     Show all 3 Subjects
Abstract:
... The classical STD NMR protocol to monitor solvent interactions in gels is strongly dependent on gelator and solvent concentrations and does not report on the degree of structuration of the solvent at the particle/solvent interface. We hypothesised that, for suspensions of large gelator particles, solvent structuration could be characterised by STD NMR when taking into account the particle-to-solve ...
DOI:
10.1016/j.jcis.2021.02.094

2. A semi-empirical model for water inflow into a tunnel in fractured-rock aquifers considering non-Darcian flow

Author:
Zhou, Jia-Qing; Liu, Hong-Bin; Li, Changdong; He, Xiang-Lan; Tang, Huiming; Zhao, Xian-Jin
Source:
Journal of hydrology 2021 v.597 pp. 126149
ISSN:
0022-1694
Subject:
equations,   etc   ; analytical methods; aquifers;     Show all 3 Subjects
Abstract:
... Water inflow into a tunnel is usually estimated by assuming that the flow follows the linear Darcy’s law. However, fluid flow in fractured-rock aquifers is prone to deviation from Darcy’s law and gives rise to nonlinear flow phenomena due to significant inertial losses. This non-Darcian effect is seldom considered when evaluating water inflow into the tunnel in a fractured-rock aquifer. In this st ...
DOI:
10.1016/j.jhydrol.2021.126149

3. High affinity of 3D spongin scaffold towards Hg(II) in real waters

Author:
Domingues, Eddy M.; Gonçalves, Gil; Henriques, Bruno; Pereira, Eduarda; Marques, Paula A.A.P.
Source:
Journal of hazardous materials 2021 v.407 pp. 124807
ISSN:
0304-3894
Subject:
equations,   etc   ; collagen; seawater; sorption;     Show all 4 Subjects
Abstract:
... This study focuses on the ability of commercial natural bath sponges, which are made from the skeletons of marine sponges, to sorb Hg from natural waters. The main component of these bath sponges is spongin, which is a protein-based material, closely related to collagen, offering a plenitude of reactive sites from the great variety of amino acids in the protein chains, where the Hg ions can sorb. ...
DOI:
10.1016/j.jhazmat.2020.124807

4. A worksheet-based tool to implement reactive transport models in COMSOL Multiphysics

Author:
López-Vizcaíno, Rubén; Yustres, Ángel; Cabrera, Virginia; Navarro, Vicente
Source:
Chemosphere 2021 v.266 pp. 129176
ISSN:
0045-6535
Subject:
equations,   etc   ; mathematical models; people;     Show all 3 Subjects
Abstract:
... The increasing needs for modelling of reactive transport phenomena in different areas of environmental modelling have led to the development of many numerical codes. However, many of them suffer from a lack of flexibility, which hinders the adaptation of the codes to new problems. Moreover, in many cases, changes can be done by a very reduced group of people, and often by a single person, the main ...
DOI:
10.1016/j.chemosphere.2020.129176

5. Optimization of thermodynamic and surface properties of ternary Ti–Al–Si alloy and its sub-binary alloys in molten state

Author:
Yadav, S.K.; Mehta, U.; Adhikari, D.
Source:
Heliyon 2021 v.7 no.3 pp. e06511
ISSN:
2405-8440
Subject:
equations,   etc   ; alloys; models; thermodynamics;     Show all 4 Subjects
Abstract:
... Thermodynamic and surface properties of the ternary system were studied at different higher temperatures (1973 K, 2073 K, 2173 K and 2273 K). The thermodynamic properties were studied using the Chou, Kohler and Toop models. Meanwhile, the surface properties were investigated using the same models plus the Butler model. The thermodynamic and surface properties of the ternary alloys computed from di ...
DOI:
10.1016/j.heliyon.2021.e06511

6. The sine-Gordon expansion method for higher-dimensional NLEEs and parametric analysis

Author:
Kundu, Purobi Rani; Fahim, Md. Rezwan Ahamed; Islam, Md. Ekramul; Akbar, M. Ali
Source:
Heliyon 2021 v.7 no.3 pp. e06459
ISSN:
2405-8440
Subject:
equations,   etc   ; fluid mechanics; optics;     Show all 3 Subjects
Abstract:
... The Estevez-Mansfield-Clarkson (EMC) equation and the (2+1)-dimensional Riemann wave (RW) equation are important mathematical models in nonlinear science, engineering and mathematical physics which have remarkable applications in the field of plasma physics, fluid dynamics, optics, image processing etc. Generally, through the sine-Gordon expansion (SGE) method only the lower-dimensional nonlinear ...
DOI:
10.1016/j.heliyon.2021.e06459

7. Integrated management systems maturity: Drivers and benefits in Indian SMEs

Author:
Vashishth, Abhishek; Chakraborty, Ayon; Gouda, Sirish Kumar; Gajanand, M.S.
Source:
Journal of cleaner production 2021 v.293 pp. 126243
ISSN:
0959-6526
Subject:
equations,   etc   ; management systems; motivation; India;     Show all 4 Subjects
Abstract:
... This study aims to assess the impact of the antecedents of Integrated Management System (IMS) implementation on the IMS maturity and its subsequent impact on operational performance in the context of Indian Small and Medium Enterprises (SMEs). Using Theory of Planned Behavior, this study develops research hypotheses linking challenges and motivation to implement IMS with IMS maturity and its impac ...
DOI:
10.1016/j.jclepro.2021.126243

8. Entropy differences between hydrides and other elements

Author:
Kojima, Yoshitsugu; Yamaguchi, Masakuni
Source:
Chemical communications 2021 v.57 no.28 pp. 3461-3463
ISSN:
1364-548X
Subject:
equations,   etc   ; entropy; liquid nitrogen; toluene;     Show all 4 Subjects
Abstract:
... The standard entropy differences between hydrides and other elements (metals, liquid N₂, toluene) ΔS were increased with the volume differences ΔV. It was found that ΔS is roughly expressed by the following equation, |ΔS| ∝ Rln|ΔV|, in which R is the gas constant. ...
DOI:
10.1039/d0cc07107b

9. Examination of the Peleg and Normand equation during relaxation of wheat: The effect of holding time

Author:
Łysiak, Grzegorz; Al Aridhee, Jawad Kadhim; Kulig, Ryszard; Różyło, Renata; Wójcik, Monika
Source:
Journal of texture studies 2021 v.52 no.2 pp. 157-168
ISSN:
0022-4901
Subject:
equations,   etc   ; deformation; models; texture; wheat;     Show all 5 Subjects
Abstract:
... In this study, we analyzed the effect of the duration of relaxation experiments on the parameters of the model proposed by Peleg and Normand. The relaxation experiments were conducted for individual intact wheat kernels in compression. Single kernels were initially loaded with a force of 20 N, then maintained at a constant deformation over time of 300 s. For the following time intervals 0–10, 0–20 ...
DOI:
10.1111/jtxs.12579

10. Disentangling the contributions of urban and production sources in short- and medium-chain chlorinated paraffin concentrations in a complex source region

Author:
Niu, Shan; Chen, Ruiwen; Hageman, Kimberly J.; Zou, Yun; Dong, Liang; Zheng, Ran; Wang, Xiaohui; Hai, Reti
Source:
Journal of hazardous materials 2021 v.405 pp. 124117
ISSN:
0304-3894
Subject:
equations,   etc   ; air; bark; trees; wind;     Show all 5 Subjects
Abstract:
... Short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were measured in tree bark samples. These samples were collected around a chemical industrial park containing several chlorinated paraffin (CP) production plants, in a nearby city (Zhengzhou), and along a transect between the industrial park and city. Theoretical air concentrations were back-calculated from co ...
DOI:
10.1016/j.jhazmat.2020.124117

11. Estimation of parameters in the Weibull model from microbial survival data obtained under constant conditions with come-up times

Author:
Zhu, Si; Campanella, Osvaldo; Chen, Guibing
Source:
Journal of food engineering 2021 v.292 pp. 110364
ISSN:
0260-8774
Subject:
equations,   etc   ; Weibull statistics; pathogen survival;     Show all 3 Subjects
Abstract:
... The Weibull model is frequently used to describe non-linear microbial survival due to its simplicity and flexibility. An essential part of developing a predictive microbiological approach is to accurately estimate survival parameters. In this study, an explicit integral representation of the Weibull model was derived from its original differential form. Calculated microbial survival curves under t ...
DOI:
10.1016/j.jfoodeng.2020.110364

12. Experimental study on vertical stress distribution underneath granular silos

Author:
Liu, Yuan-Yuan; Zhang, Ding-Li; Dai, Bei-Bing; Su, Jie; Li, Yanrong; Yeung, Albert T.
Source:
Powder technology 2021 v.381 pp. 601-610
ISSN:
0032-5910
Subject:
equations,   etc   ; materials; shape; silos; technology;     Show all 5 Subjects
Abstract:
... Present study is aimed to experimentally scrutinize the horizontal distribution of vertical stress underneath granular silos using a high-sensitivity stress sensor mat system. Two granular materials of contrasting particle shape but similar size were utilized to construct granular silos by the alleged local source method. The experimental results indicate that the average vertical stress is agreea ...
DOI:
10.1016/j.powtec.2020.11.066

13. Optimal Location of Energy Dissipation Box in Long Distance and High Drop Gravitational Water Supply System

Author:
Ni, Weixiang; Zhang, Jian; Chen, Sheng
Source:
Water 2021 v.13 no.4
ISSN:
2073-4441
Subject:
equations,   etc   ; energy; water; water supply;     Show all 4 Subjects
Abstract:
... In the long-distance and high-drop gravitational water supply systems, the water level difference between the upstream and downstream is large. Thus, it is necessary to ensure energy dissipation and pressure head reduction to reduce the pipeline pressure head. The energy dissipation box is a new type of energy dissipation and pressure head reduction device, which is widely used in the gravitationa ...
DOI:
10.3390/w13040461

14. Discharge coefficient of flow over Al-Shalalat stepped weir on Al-Khusr River

Author:
Altalib, Azza N.
Source:
Applied water science 2021 v.11 no.2 pp. 16
ISSN:
2190-5487
Subject:
equations,   etc   ; energy; irrigation; rivers; water;     Show all 5 Subjects
Abstract:
... Many hydraulic structures are constructed in an open channel according to the purposes and the nature of the region. Weir is one of these structures which is used for discharge measurements as well as rising water depth in irrigation channels. According to the crest, there are two different shapes: sharp and broad crested weir. A stepped weir is constructed to reduce scour that happened downstream ...
DOI:
10.1007/s13201-020-01342-9

15. Impact of religiosity on purchase intentions towards counterfeit products: investigating the mediating role of attitude and moderating role of hedonic benefits

Author:
Yaakop, Azizul Yadi; Hafeez, Hafiz Muhammad; Faisal, Malik Muhammad; Munir, Muhammad; Ali, Majid
Source:
Heliyon 2021 v.7 no.2 pp. e06026
ISSN:
2405-8440
Subject:
equations,   etc   ; consumer attitudes; questionnaires; Pakistan;     Show all 4 Subjects
Abstract:
... This study was aimed at exploring the impact of religiosity on purchase intention towards counterfeit products by investigating the mediating role of consumer attitude. This study investigated religiosity as an independent variable, attitude towards counterfeit as a mediator while predicting the purchase intentions of the consumers. A self-administered questionnaire using a five-point Likert scale ...
DOI:
10.1016/j.heliyon.2021.e06026

16. Length–weight relationships of six fish species from mangroves of Qinzhou Harbor, Southern China

Author:
Liu, Hao; Huang, Delian; Huang, Xin; Huang, Liangliang; Huang, Yuequn; Wu, Zhiqiang
Source:
Journal of applied ichthyology 2021 v.37 no.1 pp. 137-139
ISSN:
0175-8659
Subject:
equations,   etc   ; fish; formaldehyde; ichthyology; China;     Show all 5 Subjects
Abstract:
... The length–weight relationships (LWRs) for six species were estimated. Fish were captured in the mangroves of Qinzhou Harbour, China, but also some specimens were purchased from fishermen. The sampling was undertaken monthly between May 2011 and April 2012 using seines (mesh size 5–10 mm; height 4 m; length 400 m) and traps (mesh size 8.5 mm; 35 cm² × 10 m for one unit) at seven sampling sites. St ...
DOI:
10.1111/jai.14119

17. Particle Velocity Distribution and Its Prediction in a 14 m Two-Dimensional Circulating Fluidized Bed Riser

Author:
Wang, Chengxiu; Yang, Xiao; Wang, Min; Zhang, Jiazhi; Lan, Xingying; Gao, Jinsen; Ye, Mao; Zhu, Jesse
Source:
Industrial & engineering chemistry process design and development 2021 v.60 no.4 pp. 1901-1911
ISSN:
1520-5045
Subject:
equations,   etc   ; chemistry; prediction; process design;     Show all 4 Subjects
Abstract:
... Particle velocity (Vₚ) is investigated comprehensively in a two-dimensional circulating fluidized bed (CFB) riser with a superficial gas velocity (Ug) of 5–7 m/s and a solids circulation rate (Gₛ) up to 500 kg/m²s which are similar to the industrial operating conditions. Results indicate that the lateral profile of Vₚ is nonuniform showing roughly a “core-annulus” or parabolic trend with Gₛ less t ...
DOI:
10.1021/acs.iecr.0c05330

18. An analytical method for shallow spherical shell free vibration on two-parameter foundation

Author:
Gan, Jiarong; Yuan, Hong; Li, Shanqing; Peng, Qifeng; Zhang, Huanliang
Source:
Heliyon 2021 v.7 no.1 pp. e05876
ISSN:
2405-8440
Subject:
differential equation,   etc   ; analytical methods; vibration;     Show all 3 Subjects
Abstract:
... The free vibration control differential equation of shallow spherical shell on two-parameter foundation is a four order differential equation. Using the intermediate variable, the four order differential equation is reduced to two lower order differential equations. The first lower order differential equation is a Helmholtz equation. A new method of two-dimensional Helmholtz operator is proposed a ...
DOI:
10.1016/j.heliyon.2020.e05876

19. Mathematical Modeling of Population Dynamics Based on Recurrent Equations: Results and Prospects. Part I

Author:
Frisman, E. Ya.; Zhdanova, O. L.; Kulakov, M. P.; Neverova, G. P.; Revutskaya, O. L.
Source:
Biology bulletin of the Russian Academy of Sciences 2021 v.48 no.1 pp. 1-15
ISSN:
1062-3590
Subject:
equations,   etc   ; Biological Sciences; population dynamics;     Show all 3 Subjects
Abstract:
... Approaches to modeling population dynamics using discrete-time models are described in this two-part review. The development of the scientific ideas of discrete time models, from the Malthus model to modern population models that take into account many factors affecting the structure and dynamics, is presented. The most important and interesting results of recurrent equation application to biologi ...
DOI:
10.1134/S1062359021010064

20. Microwave power control scheme for potatoes based on dielectric loss factor feedback

Author:
Ma, Xiaotong; Luo, Guiyi; Li, Zhenfeng; Raghavan, G.S.V.; Chen, Haiying; Song, ChunFang
Source:
Journal of food engineering 2021 v.288 pp. 110134
ISSN:
0260-8774
Subject:
equations,   etc   ; potatoes; temperature; water content;     Show all 4 Subjects
Abstract:
... The dielectric properties of potatoes in the moisture content range of 8.3%–75.4% (w.b.) and the temperature range of 25 °C–85 °C were measured with a coaxial probe network analyzer. The regression equation of loss factor of potatoes with its moisture content and temperature was developed first and then introduced into an established LabVIEW control program to make dielectric loss factor as feedba ...
DOI:
10.1016/j.jfoodeng.2020.110134