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Using ultrasound to improve the sequential post-synthesis modification method for making mesoporous Y

Rongxin Zhang, Peinan Zhong, Hamidreza Arandiyan, Yanan Guan, Jinmin Liu, Na Wang, Yilai Jiao, Xiaolei Fan

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 275-287 doi: 10.1007/s11705-019-1905-1

摘要： Mesoporous Y zeolites were prepared by the sequential chemical dealumination (using chelating agents such as ethylenediaminetetraacetic acid, H EDTA, and citric acid aqueous solutions) and alkaline desilication (using sodium hydroxide, NaOH, aqueous solutions) treatments. Specifically, the ultrasound-assisted alkaline treatment (i.e., ultrasonic treatment) was proposed as the alternative to conventional alkaline treatments which are performed under hydrothermal conditions. In comparison with the hydrothermal alkaline treatment, the ultrasonic treatment showed the comparatively enhanced efficiency (with the reduced treatment time, i.e., 5 min vs. 30 min, all with 0.2 mol·L NaOH at 65°C) in treating the dealuminated Y zeolites for creating mesoporosity. For example, after the treatment of a dealuminated zeolite Y (using 0.1 mol·L H EDTA at 100°C for 6 h), the ultrasonic treatment produced the mesoporous zeolite Y with the specific external surface area ( ) of 160 m ·g and mesopore volume ( ) of 0.22 cm ·g , being slightly higher than that by the conventional method (i.e., = 128 m ·g and = 0.19 cm ·g ). The acidic property and catalytic activity (in catalytic cracking of -octane) of mesoporous Y zeolites obtained by the two methods were comparable. The ultrasonic desilication treatment was found to be generic, also being effective to treat the dealuminated Y zeolites by citric acid. Additionally, the first step of chemical dealumination treatment was crucial to enable the effective creation of mesopores in the parent Y zeolite (with a silicon-to-aluminium ratio, Si/Al= 2.6) regardless of the subsequent alkaline desilication treatment (i.e., ultrasonic or hydrothermal). Therefore, appropriate selection of the condition of the chemical dealumination treatment based on the property of parent zeolites, such as Si/Al ratio and crystallinity, is important for making mesoporous zeolites effectively.

关键词： zeolite Y     mesoporous zeolite     post-synthesis treatment     ultrasound     chemical dealumination treatment     alkaline desilication treatment    

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A global synthesis of the effectiveness and ecological impacts of management interventions for species

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1741-x

摘要：

● Spartina abundance decreases over time by chemical control.

关键词： Plant invasion     Biodiversity     Meta-analysis     Restoration     Salt marshes     Treatment timing    

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Treatment of gingival hyperplasia induced by cyclosporine A

MA Jingzhi, LI Ming, CAO Yingguang

《医学前沿（英文）》 2008年 第2卷 第3期   页码 290-294 doi: 10.1007/s11684-008-0055-5

摘要： The clinical therapy for cyclosporine A (CsA)-induced gingival hyperplasia (GH) and the pathological changes in hyperplastic gingival tissues were investigated. Nine cases of CsA-induced GH after renal transplantation were subjected to periodontal non-surgical treatment and surgical treatment and were followed up. Gingival index (GI), dental plaque index (PLI) and GH degree (GHD) at different time points were measured. Under light and electron microscopy, the pathological changes in hyperplastic gingival tissues were observed. The CsA concentrations in gingival tissues and blood were determined by using fluorescence polarization immunoassay with TDFL monoclonal antibody. The results showed that GI, PLI and GHD in patients with GH declined after periodontal treatment. Two patients suffered from different degrees of GH during the 6 months to 54 months post-transplantation. Under transmission electron microscopy, fibroblasts in the hyperplastic gingival tissues were enlarged, cytoplasmic rough endoplasmic reticula were abundant and expanded slightly, and a few fibroblasts with early apoptotic changes were seen. The concentrations of CsA in hyperplastic gingival tissues were from 351.00 to 1345.47 ng/mL, which were significantly higher than in the blood of the same patients taken at the same time points. It was concluded that GI and PLI declined after periodontal treatment in combination with surgical treatment in patients taking CsA for a long time, but in some patients, GH recurred. The fact that the concentration of CsA in hyperplastic gingival tissues is higher than in blood awaits further studies.

关键词： post-transplantation     Gingival     cytoplasmic     CsA-induced     further    

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Efficacy and safety of JAK inhibitor INC424 in patients with primary and post-polycythemia vera or post-essential

null

《医学前沿（英文）》 2016年 第10卷 第4期   页码 437-443 doi: 10.1007/s11684-016-0472-9

摘要：

A phase II study (A2202) was performed to evaluate the efficacy and safety of JAK inhibitor ruxolitinib in 63 Chinese MF patients. Ruxolitinib was given twice a day (bid) at a starting dose of 15 mg (n=25) or 20 mg (n=38) based on a baseline platelet count. About 94.7% of the patients achieved a reduction in spleen size, 27.0% of which exhibited significant reduction (≥35%) at week 24. Significant improvement in debilitating constitutional symptoms, as assessed by MFSAF v2.0, was observed in patients treated with ruxolitinib. Ruxolitinib treatment was generally well tolerated by Chinese patients. Although the treatment was associated with an increase in certain adverse events (AEs) that were established as identified risks (anemia and thrombocytopenia), these AEs were considered manageable in this clinical setting. Ruxolitinib provided substantial reductions in splenomegaly and improvements in symptoms, and was well-tolerated by Chinese patients with MF.

关键词： JAK     ruxolitinib     Chinese patients     myelofibrosis    

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Rapid alloying of CoCrFeMnNi high-entropy alloy from elemental feedstock toward high-throughput synthesis

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0727-x

摘要： High-entropy alloys (HEAs) are considered alternatives to traditional structural materials because of their superior mechanical, physical, and chemical properties. However, alloy composition combinations are too numerous to explore. Finding a rapid synthesis method to accelerate the development of HEA bulks is imperative. Existing in situ synthesis methods based on additive manufacturing are insufficient for efficiently controlling the uniformity and accuracy of components. In this work, laser powder bed fusion (L-PBF) is adopted for the in situ synthesis of equiatomic CoCrFeMnNi HEA from elemental powder mixtures. High composition accuracy is achieved in parallel with ensuring internal density. The L-PBF-based process parameters are optimized; and two different methods, namely, a multi-melting process and homogenization heat treatment, are adopted to address the problem of incompletely melted Cr particles in the single-melted samples. X-ray diffraction indicates that HEA microstructure can be obtained from elemental powders via L-PBF. In the triple-melted samples, a strong crystallographic texture can be observed through electron backscatter diffraction, with a maximum polar density of 9.92 and a high ultimate tensile strength (UTS) of (735.3 ± 14.1) MPa. The homogenization heat-treated samples appear more like coarse equiaxed grains, with a UTS of (650.8 ± 16.1) MPa and an elongation of (40.2% ± 1.3%). Cellular substructures are also observed in the triple-melted samples, but not in the homogenization heat-treated samples. The differences in mechanical properties primarily originate from the changes in strengthening mechanism. The even and flat fractographic morphologies of the homogenization heat-treated samples represent a more uniform internal microstructure that is different from the complex morphologies of the triple-melted samples. Relative to the multi-melted samples, the homogenization heat-treated samples exhibit better processability, with a smaller composition deviation, i.e., ≤ 0.32 at.%. The two methods presented in this study are expected to have considerable potential for developing HEAs with high composition accuracy and composition flexibility.

关键词： laser powder bed fusion (L-PBF)     in situ alloying     high-entropy alloys     heat treatment     rapid synthesis    

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Dynamic modelling and simulation of a post-combustion CO capture process for coal-fired power plants

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 198-209 doi: 10.1007/s11705-021-2057-7

摘要： Solvent-based post-combustion capture technologies have great potential for CO2 mitigation in traditional coal-fired power plants. Modelling and simulation provide a low-cost opportunity to evaluate performances and guide flexible operation. Composed by a series of partial differential equations, first-principle post-combustion capture models are computationally expensive, which limits their use in real time process simulation and control. In this study, we propose a first-principle approach to develop the basic structure of a reduced-order model and then the dominant factor is used to fit properties and simplify the chemical and physical process, based on which a universal and hybrid post-combustion capture model is established. Model output at steady state and trend at dynamic state are validated using experimental data obtained from the literature. Then, impacts of liquid-to-gas ratio, reboiler power, desorber pressure, tower height and their combination on the absorption and desorption effects are analyzed. Results indicate that tower height should be designed in conjunction with the flue gas flow, and the gas-liquid ratio can be optimized to reduce the reboiler power under a certain capture target.

关键词： CO2 capture     post-combustion capture     simulation     dominant factor    

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Microwave assisted synthesis of poly(2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) and itsapplication as a flocculant for wastewater treatment

Gautam SEN, G. Usha RANI, Sumit MISHRA

《化学科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 312-321 doi: 10.1007/s11705-013-1344-3

摘要： Poly(2-hydroxyethylmethacrylate) chains were grafted onto the backbone of agar using a microwave assisted method involving a combination of microwave irradiation and ceric ammonium nitrate to initiate the grafting reaction. The synthesized graft copolymers were characterized by intrinsic viscosity measurements, Fourier transform infrared spectroscopy, elemental analysis (C, H, N, O and S) and scanning electron microscopy. Ag-g-P(HEMA)-2 showed a much higher flocculation efficacy than agar. The optimized dosage of flocculation for Ag-g-P(HEMA)-2 in the wastewater was found to be 0.75 ppm. Compared to agar, Ag-g-P(HEMA)-2 was found to considerably reduce the pollutant load in the wastewater.

关键词： agar     flocculant     microwave assisted synthesis     jar test protocol     poly(HEMA) grafted agar     wastewater treatment    

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Adiponectin: mechanisms and new therapeutic approaches for restoring diabetic heart sensitivity to ischemic post-conditioning

null

《医学前沿（英文）》 2013年 第7卷 第3期   页码 301-305 doi: 10.1007/s11684-013-0283-1

摘要：

Systemic inflammatory response following myocardial ischemia-reperfusion injury (IRI) to a specific organ may cause injuries. Ischemic post-conditioning (IPostC) has emerged as a promising method for myocardial protection against IRI both in experimental and in clinical settings. Enhancement of endogenous nitric oxide (NO) is one of the major mechanisms by which IPostC confers cardioprotection. However, the sensitivity of the diabetic heart to IPostC is impaired and the underlying mechanism is unknown. Adiponectin (APN) is an adipocyte-derived plasma protein with anti-diabetic and anti-inflammatory properties. Plasma levels of APN are decreased in obese subjects and in patients with type 2 diabetes. APN supplementation has been shown to increase NO production and attenuate myocardial IRI in normal (non-diabetic) animals. However, the effect of APN on myocardial injury in diabetic subjects, especially its potential in restoring the sensitivity of the diabetic heart to IPostC has not been investigated. In the current paper, we discussed the possible reasons why the myocardium of diabetic subjects loses sensitivity to IPostC and also highlighted the potential effectiveness and mechanism of APN in restoring IPostC cardioprotection in diabetes. This review proposes to conduct studies that may facilitate the development of novel and optimal therapies to enhance cardioprotection in patients with severe diseases such as diabetes.

关键词： adiponectin     ischemic post-conditioning     ischemia reperfusion injury     diabetes    

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Internet of Things (IoT)–blockchain-enabled pharmaceutical supply chain resilience in the post-pandemic

《工程管理前沿（英文）》   页码 82-95 doi: 10.1007/s42524-022-0233-1

摘要： During the COVID-19 pandemic, the current operating environment of pharmaceutical supply chain (PSC) has rapidly changed and faced increasing risks of disruption. The Internet of Things (IoT) and blockchain not only help enhance the efficiency of PSC operations in the information technology domain but also address complex related issues and improve the visibility, flexibility, and transparency of these operations. Although IoT and blockchain have been widely examined in the areas of supply chain and logistics management, further work on PSC is expected by the public to enhance its resilience. To respond to this call, this paper combines a literature review with semi-structured interviews to investigate the characteristics of PSC, the key aspects affecting PSC, and the challenges faced by PSC in the post-pandemic era. An IoT–blockchain-integrated hospital-side oriented PSC management model is also developed. This paper highlights how IoT and blockchain technology can enhance supply chain resilience and provides a reference on how PSC members can cope with the associated risks.

关键词： pharmaceutical supply chain     Internet of Things     blockchain     resilience     post-pandemic era    

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Parametric study of hexagonal castellated beams in post-tensioned self-centering steel connections

Hassan ABEDI SARVESTANI

《结构与土木工程前沿（英文）》 2019年 第13卷 第5期   页码 1020-1035 doi: 10.1007/s11709-019-0534-6

摘要： The effects of important parameters (beam reinforcing plates, initial post-tensioning, and material properties of steel angles) on the behavior of hexagonal castellated beams in post-tensioned self-centering (PTSC) connections undergone cyclic loading up to 4% lateral drift have been investigated by finite element (FE) analysis using ABAQUS. The PTSC connection is comprised of bolted top and bottom angles as energy dissipaters and steel strands to provide self-centering capacity. The FE analysis has also been validated against the experimental test. The new formulations derived from analytical method has been proposed to predict bending moment of PTSC connections. The web-post buckling in hexagonal castellated beams has been identified as the dominant failure mode when excessive initial post-tensioning force is applied to reach greater bending moment resistance, so it is required to limit the highest initial post-tensioning force to prevent this failure. Furthermore, properties of steel material has been simulated using bilinear elastoplastic modeling with 1.5% strain-hardening which has perfectly matched with the real material of steel angles. It is recommended to avoid using steel angles with high yielding strength since they lead to the yielding of bolt shank. The necessity of reinforcing plates to prevent beam flange from local buckling has been reaffirmed.

关键词： finite element analysis     hexagonal castellated beam     parametric study     post-tensioned self-centering steel connection     steel moment-resisting frame    

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Special issue: Advancing supply chain resilience for excellence in the post-pandemic era

《工程管理前沿（英文）》 2023年 第10卷 第1期   页码 1-4 doi: 10.1007/s42524-022-0246-9

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Integrated adsorption and absorption process for post-combustion CO

Gongkui Xiao, Penny Xiao, Andrew Hoadley, Paul Webley

《化学科学与工程前沿（英文）》 2021年 第15卷 第3期   页码 483-492 doi: 10.1007/s11705-020-1964-3

摘要： This study explored the feasibility of integrating an adsorption and solvent scrubbing process for post-combustion CO capture from a coal-fired power plant. This integrated process has two stages: the first is a vacuum swing adsorption (VSA) process using activated carbon as the adsorbent, and the second stage is a solvent scrubber/stripper system using monoethanolamine (30 wt-%) as the solvent. The results showed that the adsorption process could enrich CO in the flue gas from 12 to 50 mol-% with a CO recovery of >90%, and the concentrated CO stream fed to the solvent scrubber had a significantly lower volumetric flowrate. The increased CO concentration and reduced feed flow to the absorption section resulted in significant reduction in the diameter of the solvent absorber, bringing the size of the absorber from uneconomically large to readily achievable domain. In addition, the VSA process could also remove most of the oxygen initially existed in the feed gas, alleviating the downstream corrosion and degradation problems in the absorption section. The findings in this work will reduce the technical risks associated with the state-of-the art solvent absorption technology for CO capture and thus accelerate the deployment of such technologies to reduce carbon emissions.

关键词： vacuum swing adsorption     monoethanolamine     post-combustion     CO2 capture     integrated process    

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Interactions between remote ischemic conditioning and post-stroke sleep regulation

《医学前沿（英文）》 2021年 第15卷 第6期   页码 867-876 doi: 10.1007/s11684-021-0887-9

摘要： Sleep disturbances are common in patients with stroke, and sleep quality has a critical role in the onset and outcome of stroke. Poor sleep exacerbates neurological injury, impedes nerve regeneration, and elicits serious complications. Thus, exploring a therapy suitable for patients with stroke and sleep disturbances is imperative. As a multi-targeted nonpharmacological intervention, remote ischemic conditioning can reduce the ischemic size of the brain, improve the functional outcome of stroke, and increase sleep duration. Preclinical/clinical evidence showed that this method can inhibit the inflammatory response, mediate the signal transductions of adenosine, activate the efferents of the vagal nerve, and reset the circadian clocks, all of which are involved in sleep regulation. In particular, cytokines tumor necrosis factor α (TNFα) and adenosine are sleep factors, and electrical vagal nerve stimulation can improve insomnia. On the basis of the common mechanisms of remote ischemic conditioning and sleep regulation, a causal relationship was proposed between remote ischemic conditioning and post-stroke sleep quality.

关键词： remote ischemic conditioning     sleep regulation     stroke    

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Experimental study on pile-end post-grouting piles for super-large bridge pile foundations

Weiming GONG, Guoliang DAI, Haowen ZHANG

《结构与土木工程前沿（英文）》 2009年 第3卷 第2期   页码 228-233 doi: 10.1007/s11709-009-0019-0

摘要： The application of pile-end post-grouting piles for super-large bridge pile foundations in some important projects was introduced in this paper. There are totally 21 test piles. The maximum pile diameter varies from 2.5 m to 3 m, and the maximum length is 125 m; the bearing capacity of the post-grouting piles is over ten thousands tons. Based on the test results, the bearing capacity, displacement, and bearing characteristic before and after grouting were analyzed. The results show that the bearing capacity of the piles are increased in different degrees after grouting although the technical parameters, including the patterns of grouting pipes, pressure, dosages of cement, duration of grouting lasting time, are different. However, the obtained values are very discrete. In addition, the calculation formula for the post-grouting piles under specified grouting condition was deduced based on the statistics analysis results of 57 test piles. The research results have been applied in the design of bridge foundation.

关键词： self-balanced testing technique     pile-end post-grouting     bearing capacity     grouting technology    

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Secondary transfer length and residual prestress of fractured strand in post-tensioned concrete beams

Lizhao DAI; Wengang XU; Lei WANG; Shanchang YI; Wen CHEN

《结构与土木工程前沿（英文）》 2022年 第16卷 第3期   页码 388-400 doi: 10.1007/s11709-022-0809-1

摘要： An experimental study is performed on five post-tensioned concrete beams to explore the effects of different fracture positions on secondary transfer length and residual prestress of fractured strand. A numerical model is developed and used to predict the secondary transfer length and residual prestress of fractured strand in post-tensioned concrete beams. The model change interaction, which can deactivate and reactivate the elements for simulating the removal and reproduction of parts of the model, is used to reproduce the secondary anchorage of fractured strand. The numerical model is verified by experimental results. Results shows that the fractured strand can be re-anchored in concrete through the secondary anchorage, and the secondary transfer length of fractured strand with the diameter of 15.2 mm is 1133 mm. The residual prestress of fractured strand increases gradually in the secondary transfer length, and tends to be a constant beyond it. When the fractured strand is fully anchored in concrete, a minor prestress loss will appear, and the average prestress loss is 2.28% in the present study.

关键词： post-tensioned concrete beams     strand fracture     secondary transfer length     residual prestress    

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标题 作者 时间 类型 操作

Using ultrasound to improve the sequential post-synthesis modification method for making mesoporous Y

Rongxin Zhang, Peinan Zhong, Hamidreza Arandiyan, Yanan Guan, Jinmin Liu, Na Wang, Yilai Jiao, Xiaolei Fan

期刊论文

A global synthesis of the effectiveness and ecological impacts of management interventions for species

期刊论文

Treatment of gingival hyperplasia induced by cyclosporine A

MA Jingzhi, LI Ming, CAO Yingguang

期刊论文

Efficacy and safety of JAK inhibitor INC424 in patients with primary and post-polycythemia vera or post-essential

null

期刊论文

Rapid alloying of CoCrFeMnNi high-entropy alloy from elemental feedstock toward high-throughput synthesis

期刊论文

Dynamic modelling and simulation of a post-combustion CO capture process for coal-fired power plants

期刊论文

Microwave assisted synthesis of poly(2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) and itsapplication as a flocculant for wastewater treatment

Gautam SEN, G. Usha RANI, Sumit MISHRA

期刊论文

Adiponectin: mechanisms and new therapeutic approaches for restoring diabetic heart sensitivity to ischemic post-conditioning

null

期刊论文

Internet of Things (IoT)–blockchain-enabled pharmaceutical supply chain resilience in the post-pandemic

期刊论文

Parametric study of hexagonal castellated beams in post-tensioned self-centering steel connections

Hassan ABEDI SARVESTANI

期刊论文

Special issue: Advancing supply chain resilience for excellence in the post-pandemic era

期刊论文

Integrated adsorption and absorption process for post-combustion CO

Gongkui Xiao, Penny Xiao, Andrew Hoadley, Paul Webley

期刊论文

Interactions between remote ischemic conditioning and post-stroke sleep regulation

期刊论文

Experimental study on pile-end post-grouting piles for super-large bridge pile foundations

Weiming GONG, Guoliang DAI, Haowen ZHANG

期刊论文

Secondary transfer length and residual prestress of fractured strand in post-tensioned concrete beams

Lizhao DAI; Wengang XU; Lei WANG; Shanchang YI; Wen CHEN

期刊论文