FUEL
·
2023
·
IF 7.4
Yang Liu,Chengxuan Wu,Xiaofang Lv,Hui Du,Qianli Ma,Chuanshuo Wang,Shidong Zhou,Bohui Shi,Shangfei Song,Jing Gong,Jimiao Duan
During deep-sea and ultra-deep-sea oil and gas exploitation, multiphase transmission lines are prone to be clogged by sediments produced by the various components in crude oils under extreme subsea conditions, such as hydrates, wax, resins, and asphaltenes. The pipelines face higher plugging risks when these deposits exist simultaneously. In order to elucidate the effects of wax and anti-agglomerants (AA) on hydrate growth and aggregation, microscopic morphology observation and cohesive force measurement of cyclopentane hydrate particles were conducted through a piece of equipment similar to the micromechanical force (MMF) apparatus. Results showed that in the low concentration of AA (0.05 wt%), hydrate particles experienced an approximately 10 % reduction in the profile area after converting water droplets to hydrate particles. Furthermore, the cohesive force between hydrate particles decreased from 8.57 ± 0.90 mN/m to 3.51 ± 0.43 mN/m as the AA concentration increased from 0.05 to 0.2 wt%. On the other hand, the presence of wax significantly altered the morphologies of hydrate particles. When wax coexisted with AA, the hydrate cohesive force was reduced by wax under low AA concentration (0.05 wt%) but increased under higher AA concentration. For a given concentration of AA, the hydrate cohesive force increased with the increasing wax content (from 0.1 to 0.3 wt%), indicating that wax crystals weakened the efficiency of AA, such as Span 80. Additionally, the effect of surface wetness of waxy hydrate particles on their cohesion was also investigated. The liquid bridge appeared between wet waxy hydrate particles, while the solid–solid contact existed between dry waxy hydrate particles. The cohesive force between dry waxy hydrate particles was smaller. Either liquid bridge or solid–solid contact that dominated hydrate cohesive force was affected by wax.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Acta Biomaterialia
·
2022
·
IF 10.633
Longyi Nan,Jie Liu,Chao Liu,Peng Quan,Jianpeng Guo,Liang Fang
Pressure-sensitive adhesives are critical to the product's safety, efficacy, and quality in transdermal drug delivery systems. However, many defects of transdermal patches ( e.g. , insufficient adhesion, patch displacement, and “dark ring” phenomenon) remain. Herein, the N -[tris(hydroxymethyl)methyl]acrylamide (NAT)-modified acrylic pressure-sensitive adhesive coordinated with Fe(III) (AA-NAT/Fe 3+ ) was creatively proposed. Results demonstrated that the adhesiveness and cohesiveness of the optimized AA-NAT/Fe 3+ were higher by 1.8- and 9.7-fold, respectively, than those of commercially available DURO-TAK® 87-4098 due to the hydrogen bonding interaction of NAT-skin interface and coordination of NAT-Fe 3+ . Moreover, compared with that of DURO-TAK® 87-4098, the adhesion time of AA-NAT/Fe 3+ on the human forearm was remarkably prolonged, and no “dark ring” phenomenon was observed for AA-NAT/Fe 3+ after removal. After clonidine (CLO) was loaded into AA-NAT/Fe 3+ , controlled drug release and a drug transdermal behavior were endowed for CLO@AA-NAT/Fe 3+ in vitro and in vivo . AA-NAT/Fe 3+ still maintained superiority in adhesion and cohesion properties after CLO loading. These observations would contribute to the development of pressure-sensitive adhesives with outstanding adhesion and cohesion for transdermal patches. Statement of significance This N -[tris(hydroxymethyl)methyl]acrylamide-modified acrylic pressure-sensitive adhesive coordinated with Fe(III) has enhanced adhesion and cohesion properties, which provide a simple but effective strategy to solve the problems ( e.g. , insufficient adhesion, patch displacement, and “dark ring” phenomenon) in existing transdermal patches.
研究领域:
材料科学
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药剂学
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生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MANAGEMENT IN ENGINEERING
·
2021
·Vol. 37
·期 5
·04021045
·
IF 6.853
Qi Liang,Mei-yung Leung,Shang Zhang
Construction professionals (CPs) usually bear significant responsibilities for the achievement of project success and, thus, have long experienced numerous workplace stressors in the demanding construction industry. The perception of stressors and, in turn, the generation of stress is largely affected by an individual’s socioeconomic background and cultural values. However, previous research mainly examined the factors for CPs’ stress in a single location. Little is known about regional differences in stressor-stress patterns globally. To better manage stress and enhance the well-being of CPs worldwide, comprehensively examining the stressor-stress interaction of CPs through a cross-regional study is necessary. This research involved a questionnaire survey with more than three hundred and fifty CPs from Hong Kong (HK) and Suzhou. A series of statistical analyses on the collected data produced a number of major findings about the stressors and stress experienced by CPs in the two cities: (1) the HK CPs experienced a higher level of objective stress but a lower level of subjective stress than their Suzhou counterparts did; (2) the HK and Suzhou CPs faced different stressors at work; (3) work overload and poor environment were critical stressors for both the HK and Suzhou CPs; and (4) group cohesion significantly affected only the stress of Suzhou CPs. Practical suggestions were provided for managing CPs’ stressors and stress, including realistic job assignments and organizing of frequent social gatherings, team-building activities, stress management seminars, and training. This study reveals different patterns of stressor-stress interactions for CPs in the two typical developed regions, which might inspire a future comparative study to explore the underlying mechanisms for CPs’ stress in the context of different regions globally. This study further extends the body of knowledge on global stress management in the construction management field and is valuable to improving the effectiveness of existing stress management practices.
研究领域:
建筑工程管理
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职业健康心理学
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组织行为学
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压力管理
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跨文化研究
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劳动卫生
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项目管理
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社会流行病学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Huimin Tian,Yachun Gu,Zili Lv,Liang Wang
Yoghurt fermented by Leuconostoc mesenteroides XR1 from Kefir grains was found to produce a unique silk drawing phenomenon. This property was found to be associated with the exopolysaccharides (EPS), X-EPS, produced by strain XR1. In order to better understand the mechanism that produced this phenomenon, the X-EPS was extracted, purified and characterized. The molecular weight and monosaccharide composition were determined by size exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS) and ion chromatography (IC) analysis, respectively. The results showed that its molecular weight was 4.183 × 10 6 g/mol and its monosaccharide composition was glucose, and glucuronic acid , with the contents of 567.6148 and 0.2096 μg/mg, respectively. FT-IR and NMR analyses showed that X-EPS was an α-pyranose polysaccharide and was composed of 92.22 % α-(1 → 6) linked d -glucopyranose units and 7.77 % α-(1 → 3) branching. Furthermore, it showed a chain-like microstructure with branches in atomic force microscopy (AFM) and scanning electron microscopy (SEM) experiments. These results suggested that the unique structure of X-EPS, gave the yoghurt a strong viscosity and cohesiveness, which resulted in the silk drawing phenomenon. This work suggested that X-EPS holds the potential for food and industrial applications.
研究领域:
食品科学
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微生物学
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聚合物化学
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生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Functional Foods
·
2024
·
IF 3.8
Fang Shi,Yong-Sheng Gao,Shu-Mei Han,Huan Shi,Qing-Sheng Hou,Yang Gao,Xiao-Wen Wen,Zhen-Yu Zhu,Kai Liu,Wei-Peng Gong,Ben-Shi Wang,Xin Liu,Lei Zou
There is a growing amount of research that highlights the significant connection between the development of colitis and both metabolic imbalance and the inflammatory response. Tagatose, an inherent sweetening agent and alternative to sugar, plays a crucial role in the biosynthesis of several chemicals and metabolic pathways in living organisms. However, the specific biochemical mechanism via which tagatose hinders colitis is still not understood. According to recent study, tagatose plays a crucial role in safeguarding the integrity of tight junctions inside the intestinal mucosal barrier. Furthermore, it is crucial to acknowledge the presence of a correlation between the severity of inflammatory bowel disease (IBD) and the occurrence of colorectal cancer (CRC), chemically-induced colitis in rodents, and reduced blood levels of tagatose. The treatment of tagatose resulted in a decrease in intestinal mucosal injury in mice with colitis, regardless of whether it was caused by dextran sodium sulfate (DSS) or spontaneous colitis in IL-10 -/- mice and C3H/HeJBir mice. The introduction of tagatose in a colitis model triggers a cascade of events, wherein it hinders the expulsion of cathepsin B and enhances lysosomal cohesiveness. The aforementioned method successfully inhibits the activity of myosin light chain kinase (MLCK) in the context of intestinal epithelial damage, hence impeding the deterioration of tight junction integrity and the initiation of mitochondrial dysfunction. In summary, the outcomes of the study have provided empirical evidence that substantiates the beneficial effects of tagatose in mitigating the progression of colitis. The ability to prevent the disruption of the intestinal barrier is responsible for this achievement. Hence, tagatose has promise as a therapeutic adjunct for the management of colitis.
研究领域:
胃肠病学
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药理学
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免疫学
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细胞生物学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）