CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Jinbang Wang,Yong Cheng,Lianwang Yuan,Dongyu Xu,Peng Du,Pengkun Hou,Zonghui Zhou,Xin Cheng,Shuai Liu,Yuguang Wang
Nano-materials modified cement-based materials have attracted wide attention due to their advantages of improving early strength and durability. However, few studies have been conducted on influence of nano-materials on chemical shrinkage of paste and volume shrinkage of concrete. Therein, the influence rules of nano-silica on chemical shrinkage of paste and volume shrinkage of concrete and its action mechanism have been explored and discussed. The result indicated that added nano-silica aggravated the chemical shrinkage of paste and volume shrinkage of the concrete. The paste chemical shrinkage and concrete volume shrinkage increased with the amount of nano-silica in particular as presented in early stage. The chemical shrinkage of cement at 3d and 28d increased by 93.7% and 57.5% respectively, when adding 1.2% nano-silica. Correspondingly, the 1d, 7d and 60d volume shrinkage of concrete increased by 82.1%, 66.7% and 16.7% respectively. The action mechanism of shrinkage intensification is mainly the pozzolanic effect, nucleation effect and acceleration hydration effect of nano-silica, which accelerated the cement hydration.
研究领域:
土木工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Sustainable Metallurgy
·
2025
·
IF 3.2
Ma Kaihui,Wu Qinghui,Fang YunPeng,Deng Junyi,Zheng Kui,Qiu Shuxing,Chen Mao,Xu Jian
The issue of carbon emissions in the iron-making process is receiving increasing attention, and the utilization of hydrogen (H 2 )-reduced iron ore presents an appealing prospect for application. Iron oxides are the primary components involved in the iron-making process, and their reduction in H 2 holds significant research value. In this work, the softening–melting behaviors of quaternary/quinary-FeO-rich oxides in four different gases, namely 100%N 2 , 10%H 2 + 90%N 2 , 40%CO + 60%N 2 , and 10H 2 + 40%CO + 50%N 2 , above 900°C are studied by simulating the cohesive zone of blast furnace. Compared to CO, H 2 exhibits a higher reducing capacity and can achieve a faster reduction of metal iron. However, due to its inability to promote carburizing and further liquation of metal iron, iron remains in a dense metallic state within the packed bed, hindering its further reduction into iron oxide particles and consequently slowing down the shrinkage of the packed bed. Delaying the initial temperature of reaccelerated shrinkage to more than 1300°C also reduces the pressure drop within the packed bed. Its limited ability for liquid phase generation plays a positive role in influencing both the height contraction and permeability reduction of the packed bed. Furthermore, the formed spinel phase in H 2 with high melting point did not shrink until the temperature was increased to 1400°C, and a sudden increase in shrinkage rate (SR) to 0.12%/°C or above was observed. Graphical
研究领域:
冶金学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Neurogastroenterology and Motility
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2016
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IF 1.817
Hongfei Li,Ji-Hong Chen,Zixian Yang,Min Huang,Yuanjie Yu,Shiyun Tan,Hesheng Luo,Jan D Huizinga
Background/Aims Neurotensin is a gut-brain peptide with both inhibitory and excitatory actions on the colonic musculature; our objective was to understand the implications of this for motor patterns occurring in the intact colon of the rat. Methods The effects of neurotensin with concentrations ranging from 0.1–100 nM were studied in the intact rat colon in vitro, by investigating spatio-temporal maps created from video recordings of colonic motility before and after neurotensin. Results Low concentration of neurotensin (0.1–1 nM) inhibited propagating long distance contractions and rhythmic propagating motor complexes; in its place a slow propagating rhythmic segmental motor pattern developed. The neurotensin receptor 1 antagonist SR-48692 prevented the development of the segmental motor pattern. Higher concentrations of neurotensin (10 nM and 100 nM) were capable of restoring long distance contraction activity and inhibiting the segmental activity. The slow propagating segmental contraction showed a rhythmic contraction—relaxation cycle at the slow wave frequency originating from the interstitial cells of Cajal associated with the myenteric plexus pacemaker. High concentrations given without prior additions of low concentrations did not evoke the segmental motor pattern. These actions occurred when neurotensin was given in the bath solution or intraluminally. The segmental motor pattern evoked by neurotensin was inhibited by the neural conduction blocker lidocaine. Conclusions Neurotensin (0.1–1 nM) inhibits the dominant propulsive motor patterns of the colon and a distinct motor pattern of rhythmic slow propagating segmental contractions develops. This motor pattern has the hallmarks of haustral boundary contractions.
研究领域:
生理学
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胃肠病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DENTAL MATERIALS
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2025
·
IF 6.3
Qingyang Zhou,Jiwei Lin,Qifang Li
Objectives The aim of this study was to develop a new composite resin to solve the problem of volume shrinkage of conventional dental restorative composite resins during the curing process in order to improve their mechanical properties and reduce the risk of restoration failure. Methods We synthesized the mercapto-alkenyl click chemical reaction product (MN-POSS) of acrylate-based POSS (MAP-POSS) with N-Acetylcysteine (NAC) using a bifunctional polysilsesquioxane modification technique and improved its dispersion in the resin matrix by physicochemical methods. In addition, methacrylate-based epoxy POSS (ME-POSS) was further synthesized and used to modify acrylate dental resins to form a free radical-cation hybrid light-curing system. Results The results showed that the composites modified with MN-POSS significantly improved mechanical strength, while the application of ME-POSS effectively reduced polymerization shrinkage, improved the water absorption and dissolution properties of the materials, and enhanced mechanical properties and hardness. This study provides new ideas and material solutions to improve the performance of dental restorative materials. Significance Both of these improved solutions demonstrate the potential of bifunctional POSS as a modified filler, providing new ideas and methods for the design of future dental restorative materials.
研究领域:
材料科学
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牙医学
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高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nutrients
·
2023
·Vol. 15
·期 8
·1889
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IF 5.9
Tae Sik Sung,Seung-Bum Ryoo,Chang-Hyun Lee,Seon-Min Choi,Joo-Won Nam,Hyun-Bok Kim,Ji young Lee,Jung-Dae Lim,Kyu Joo Park,Hyun-Tai Lee
The fruit ofMorus albaL. (MAF) has been consumed as a food worldwide. MAF has also been widely used in traditional medicine for thousands of years in East Asia, and its diverse bioactivities have been reported in numerous publications. However, no prokinetic activity has been reported for MAF or its components. In the present study, therefore, we investigated the effects of MAF on gastrointestinal motor function by measuring the intestinal transit rate (ITR) of Evans blue in mice in vivo. The ITR values accelerated by MAF were significantly higher than those accelerated by cisapride or metoclopramide, suggesting that MAF has potential as a new prokinetic agent to replace cisapride and metoclopramide. We also investigated the effects of MAF on myogenic and neurogenic contractions in human intestinal smooth muscles by measuring spontaneous contractions of smooth muscle strips, smooth muscle contractions induced by neural stimulation, and migrating motor complexes from intestinal segments in the human ileum and sigmoid colon in situ. MAF increased both myogenic and neurogenic contractions to enhance ileal and colonic motility in the human intestine. Taken together, these results indicate that MAF enhanced intestinal motility by increasing both myogenic and neurogenic contractions, thereby accelerating the ITR.Keywords:intestinal transit;Morus alba;mulberry fruit;myogenic contraction;neurogenic contraction;prokinetic;smooth muscle
研究领域:
药理学
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胃肠病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EXPERIMENTAL NEUROLOGY
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2024
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IF 4.6
Jing Qiu,Yi-Han Wang,Xiu-Ming Wang,Hui-Sheng Chen
The pericytes (PCs) surrounding capillaries are vital regulators of capillary constriction. Persistent PC contraction results in the increased capillary constriction, therefore leading to the impaired cerebral blood flow (CBF) recovery after reperfusion and worsening the clinical outcomes in stroke patients. However, the potential determinants of PC functions during ischemia/reperfusion are poorly understood. Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit Delta (PIK3CD/PI3Kδ) is a crucial factor involved with neuronflammation during ischemic stroke. PI3Kδ has shown the expression in PCs, while its effect on PC functions has not been explored yet. In this study, a rodent ischemia/reperfusion model was established in C57BL/6 mice via transient middle cerebral artery occlusion and reperfusion (MCAO/R). The PI3Kδ expression in ischemic penumbra was remarkably upregulated following MCAO/R induction. PI3Kδ inhibitor CAL-101 improved the CBF recovery, ischemic brain injury, and suppressed capillary constriction in MCAO/R mice. Besides, the production of tumor necrosis factor alpha (TNF-α), an inducer for tissue injury, and the expression of transient receptor potential vanilloid type 2 (TRPV2), a channel protein permitting calcium (Ca 2+ ) uptake, were significantly reduced in ischemic penumbra after CAL-101 treatment. In vitro, oxygen-glucose deprivation and reoxygenation (OGD/R) enhanced the expression of PI3Kδ and TRPV2 in primary mouse PCs. CAL-101 suppressed the TNF-α-induced TRPV2 expression in OGD/R-treated PCs, thus inhibiting the Ca 2+ uptake and PC contraction. Collectively, this study suggests that PI3Kδ is a critical regulator of PC function during ischemic stroke.
研究领域:
神经科学
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药理学
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细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Cells
·
2024
·Vol. 13
·期 20
·1697
·
IF 5.1
Kai Ni,Bo Che,Rong Gu,Chunhong Wang,Yan Pan,Jingjing Li,Lei Liu,Mingzhi Luo,Linhong Deng
Severe asthma is characterized by increased cell volume (hypertrophy) and enhanced contractile function (hyperresponsiveness) of the airway smooth muscle cells (ASMCs). The causative relationship and underlying regulatory mechanisms between them, however, have remained unclear. Here, we manipulated the single-cell volume of in vitro cultured human ASMCs to increase from 2.7 to 5.2 and 8.2 × 103μm3as a simulated ASMC hypertrophy by culturing the cells on micropatterned rectangular substrates with a width of 25 μm and length from 50 to 100 and 200 μm, respectively. We found that as the cell volume increased, ASMCs exhibited a pro-contractile function with increased mRNA expression of contractile proteins, increased cell stiffness and traction force, and enhanced response to contractile stimulation. We also uncovered a concomitant increase in membrane tension and Piezo1 mRNA expression with increasing cell volume. Perhaps more importantly, we found that the enhanced contractile function due to cell volume increase was largely attenuated when membrane tension and Piezo1 mRNA expression were downregulated, and an auto-regulatory loop between Piezo1 and YAP mRNA expression was also involved in perpetuating the contractile function. These findings, thus, provide convincing evidence of a direct link between hypertrophy and enhanced contractile function of ASMCs that was mediated via Piezo1 mRNA expression, which may be specifically targeted as a novel therapeutic strategy to treat pulmonary diseases associated with ASMC hypertrophy such as severe asthma.
研究领域:
肺生物学
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细胞生物学
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分子生物学
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生物物理学
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呼吸医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Weijun Deng,Fucheng Wei,Jing Hu
In many animals, tough skeletal muscle contraction occurs, producing a strong force through myofilaments attaching to and sliding on fibrous actin filaments. In contrast, the strength of typical synthetic hydrogels is facilitated mainly by polymeric chains. We propose a strategy for developing strong and tough hydrogels in which the side groups on polymeric chains strongly interact with dispersing medium. The hydrogels are fabricated with a polyacrylamide–alginate double network in a choline chloride saturated solution. The hydrogels are not only highly transparent, tough, fatigue-resistant, self-recovering, self-healing, and adhesive but also water-retentive, antifreezing, and conductive. The hydrogels are strengthened by hydrogen bonds in dispersing medium with a clathrate framework structure. This work may inspire the development of tough and conductive gels for applications of e-skins, soft robots, and intelligent devices.
研究领域:
材料科学
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生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
World Journal of Gastrointestinal Surgery
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2023
·
IF 2
Fan Ding,Run Guo,Fang Chen,Li-Ping Liu,Zheng-Yu Cui,Yi-Xing Wang,Gang Zhao,Hai Hu
BACKGROUND Impaired interstitial cells of Cajal (ICCs) are central to the pathophysiology of acute cholecystitis (AC). Common bile duct ligation is a common model of AC, producing acute inflammatory changes and decrease in gallbladder contractility. AIM To investigate the origin of slow wave (SW) in the gallbladder and the effect of ICCs on gallbladder contractions during the process of AC. METHODS Methylene blue (MB) with light was used to establish selective impaired ICCs gallbladder tissue. Gallbladder motility was assessed using the frequency of SW and gallbladder muscle contractility in vitro in normal control (NC), AC12h, AC24h, and AC48h groups of guinea pigs. Hematoxylin and eosin and Masson-stained gallbladder tissues were scored for inflammatory changes. ICCs pathological changes alterations were estimated using immunohistochemistry and transmission electron microscopy. The alterations of c-Kit, α-SMA, cholecystokinin A receptor (CCKAR), and connexin 43 (CX43) were assessed using Western blot. RESULTS Impaired ICCs muscle strips resulted in the decrease in gallbladder SW frequency and contractility. The frequency of SW and gallbladder contractility were significantly lower in the AC12h group. Compared with the NC group, the density and ultrastructure of ICCs were remarkably impaired in the AC groups, especially in the AC12h group. The protein expression levels of c-Kit were significantly decreased in the AC12h group, while CCKAR and CX43 protein expression levels were significantly decreased in the AC48h group. CONCLUSION Loss ICCs could lead to a decrease in gallbladder SW frequency and contractility. The density and ultrastructure of ICCs were clearly impaired in the early stage of AC, while CCKAR and CX43 were significantly reduced at end stage.
研究领域:
胃肠病学
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生理学
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病理生理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2025
·
IF 8.9
Fengdong Teng,Na Li,Ying Yuan,Junrong Yu,Yan Wang,Zuming Hu
The complex preparation process and high shrinkage of poly(p-phenylene terephthalamide) (PPTA) aerogel limit its wider application. Herein, PPTA and heterocyclic aramid (HPPTA) prepolymer were secondary polymerized to obtain Block-PPTA (BPPTA) with both rigid and flexible segments in the molecular chain. The rigid and flexible segments in molecular chain under non-solvent enable the rapid transformation of BPPTA solutions into well-shaped BPPTA gels. The BPPTA aerogel exhibits the advantages of low shrinkage, high thermal insulation, and high mechanical strength. Then, a small amount of MXene and AgNWs were attached to the surface of BPPTA aerogels by layer-by-layer spraying method, which not only enhanced the flame retardancy capability of the aerogels, but also made organic aerogels possible to be applied in the fields of electromagnetic interference shielding and thermoelectric conversion. This work provides an ideal strategy for the efficient preparation of low shrinkage para aramid aerogels and expands the application areas of aerogels.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2016
·Vol. 8
·期 41
·17881-17886
·
IF 7.76
Xiaogang Gu,Qingxia Fan,Feng Yang,Le Cai,Nan Zhang,Wenbin Zhou,Weiya Zhou,Sishen Xie
Hybrid hydro-responsive actuators are developed by infiltrating carbon nanotube yarns using poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). These actuators demonstrate impressive rotation and contraction in response to water due to volumetric expansion of the helical arrangement of carbon nanotubes. The total torsional stroke is 3720 revolutions per m and the simultaneously generated contractive strain reaches 24% at a paddle-to-yarn mass ratio of 350. The contraction output can furthermore be significantly enhanced by constraining the rotational motion and it reaches 68% with an applied stress of 1 MPa. Additionally, hybrid yarns exhibit an approximately linear response to humidity changes and show extra capability of electrical actuation, which, combined with the excellent hydro-actuation performance, endow them with great potential for a variety of applications including artificial muscles, hydro-driven generators, moisture switches and microfluidic mixers.
研究领域:
材料科学
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生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Kaihui Ma,Junyi Deng,Qinghui Wu,Peng Hu,Shuxing Qiu,Mao Chen,Jian Xu
Using clean energy in the ironmaking industry is expected to reduce the negative impacts on our environment. H 2 , one of the most important clean energies, has a great potential to partially replace CO in the blast furnace process, thus cutting down CO 2 emission. In order to unravel the distinct effects on the shrinkage behaviour between CO and H 2 , four binary- FeO-rich oxides and four ternary- FeO-rich oxides were employed to compare their performance under the simulated blast furnace cohesive zone conditions. The results show that the formed olivine and solid solution have the intention to dominate the shrinkage of packed bed below 900 °C, while the formed spinel compounds with higher melting point determine the shrinkage above 1300 °C. In comparison to CO, H 2 has a faster gaseous reduction rate. Therefore, the higher quantity of reduced iron and less disintegration of coke in the packed bed simultaneously suppresses the shrinkage between 900 °C and 1000 °C. Besides, the much slower iron carbonization rate in H 2 postpones the re-accelerating of shrinkage as a result of melting and dripping to higher temperatures.
研究领域:
冶金学
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环境科学
✓ 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）