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Role of Calcination Temperature on Isosorbide Production from Sorbitol Dehydration over the Catalyst Derived from Ce(IV)Sulfate

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Journal of Renewable Materials 2023年第7期11卷 2985-3000页

作者： Medta Boupan Kanyapak Prompang Achiraya Chompunuch Piwat Boonma Arthit Neramittagapong Somnuk Theerakulpisut Sutasinee Neramittagapong Department of Chemical Engineering Faculty of EngineeringKhon Kaen UniversityKhon KaenThailand Research Center for Environmental and Hazardous Substance Management(EHSM) Khon Kaen UniversityKhon KaenThailand Center of Excellence on Hazardous Substance Management(HSM) PathumwanBangkokThailand Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC)Chemical Engineering Faculty of EngineeringChulalongkorn UniversityPatumwanBangkokThailand Energy Management and Conservation Office Faculty of EngineeringKhon Kaen UniversityKhon KaenThailand

Isosorbide is a multi-purpose chemical that can be produced from renewable resources.Specifically,it has been investigated as a replacement for toxic bisphenol A(BPA)in the production of polycarbonate(PC).In this study,the synthesis of isosorbide by sorbitol Dehydration using a cerium-based catalyst derived from calcined cerium(IV)sulfate(300°C,400°C,450°C,500°C,and 650°C)was investigated.The reaction occurred in a high-pressure reactor containing nitrogen gas.Advanced instrumental techniques were applied to analyze the characteristics of the calcined catalyst.The results showed that the calcined catalysts demonstrated different crystalline structures and sulfate species at different temperatures.However,the acidic properties(strength and amount)of the catalyst did not change with the calcination temperature.The cerium(IV)sulfate calcined at 400°C exhibited the best catalytic performance,achieving the highest isosorbide yield(55.7%)and complete conversion of sorbitol at 180°C,20 bar of N2,and 6 h using CeSO-400.The presence of a sulfate group on the catalyst was the most important factor in determining the catalytic performance of sorbitol Dehydration to isosorbide.This work suggests that CeSO-400 catalysts may play an important role in reducing reaction conditions.

关键词： Cerium(IV)sulfate isosorbide sorbitol Dehydration

A thermodynamic-based model for modeling thermo-elastoplastic behaviors of saturated clayey soils considering bound water Dehydration

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第6期15卷 1535-1546页

作者： Mohammadhossein Sojoudi Biao Li Department of Building Civil and Environmental EngineeringConcordia UniversityMontrealQuebecCanada

The non-isothermal deformation of soft mudrocks or clay soils is one of the most critical issues in energy and environmental related geotechnics.Clay-related geomaterials hold complex microstructure and mineral composition,which brings difficulty in investigating their thermo-mechanical behaviors.Previous studies pay little attention to the difference between a thermal plastic strain and the strain from clay Dehydration.In this study,a new constitutive model is proposed for describing the thermoelastoplastic behaviors of clayey soils under water-saturated condition.The effect of temperature variation and mechanical loading on elastoplastic strains and Dehydration are investigated.The thermodynamics laws and the unconventional plasticity are applied to quantify the thermo-mechanical behavior.The irreversible strain is captured by using Cam-Clay plasticity and subloading yield surface concept.The Dehydration strain is described by utilizing a novel method based on generalized thermodynamics approach and Helmholtz free energy function.The internal variables,and the first and second laws of thermodynamics are applied in the model.The hardening rule is established by implementing the laws of physical conservation,energy dissipation,and plastic flow.The proposed model is validated using specially designed thermal consolidation tests on laboratory prepared heavily consolidated clayey soils and some published data of clayey soils with different geological origins.

关键词： Thermo-mechanical process Subloading yield surface Energy methods Clay-bound water Dehydration

Feasibility analysis and process simulation of CO_(2) Dehydration using triethylene glycol for CO_(2) pipeline transportation

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Chinese Journal of Chemical Engineering 2021年第12期34卷 179-186页

作者： Shupanxiang Chen Guangying Chen Xiaolan Zhao Xiao Luo Hongxia Gao Wensheng Li Zhiwu Liang Joint International Center for CO_(2)Capture and Storage(iCCS) Provincial Hunan Key Laboratory for Cost-effective Utilization of Fossil Fuel Aimed at Reducing Carbon-dioxide EmissionsDepartment of Chemical EngineeringCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

The operation of Dehydration is very important in the process of gas transportation. This study aims to evaluate the application feasibility of CO_(2) Dehydration using triethylene glycol, which is also called TEG for short. Aspen Plus software was used to simulate the Dehydration process system of CO_(2) gas transportation using TEG Dehydration. Parameter analysis and process improvement were carried out for the simulation of Dehydration process. At first, a sensitivity analysis was conducted to analyze and optimize operating conditions of conventional CO_(2)-TEG Dehydration process system. Subsequently, a recycle unit was introduced into the conventional CO_(2)-TEG Dehydration process system, it can be found that the improved process system with the recycle unit has a higher CO_(2) recovery rate which was about 9.8% than the conventional one. Moreover, the improved process system showed excellent operation stability through the comparison of simulation results of several processes with various water contents in their feed gases. Although the energy consumption is increased by about 2%, the improved process was economically and technically feasible for the long-term availability of CO_(2) pipeline transportation. The simulated results showed that the improved CO_(2)-TEG process system has promising application prospects in CO_(2) Dehydration of CO_(2) gas transportation with high stability.

关键词： Carbon dioxide Dehydration Simulation Triethylene glycol Process system

Effect of purification,Dehydration,and coagulation processes on the optical parameters of biological tissues

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Chinese Optics Letters 2021年第1期19卷 69-74页

作者： Halil Arslan Bahar Pehlivanoz Faculty of Technology Electrical and Electronics Engineering DepartmentSakarya University of Applied SciencesSakaryaTurkey

In this study,the effects of purification,Dehydration,and coagulation processes on the absorption and reduced scattering coefficients of chicken liver tissues have been investigated by using a single integrating sphere system.The purification process performed on the tissue samples to remove blood residue has been found to cause a slight change in the optical parameters.Although the Dehydration process brings about an increase in the absorption coefficient due to the water loss,no direct relationship has been observed between the reduced scattering coefficient and the Dehydration level of the tissue.In addition,it has been observed that there was a relatively small increase in the absorption coefficient and a significant increase in the reduced scattering coefficient after the coagulation process.Therefore,it can be said that the optical penetration depth decreased significantly after Dehydration and coagulation processes unlike blood purification.Moreover,fluence rate distributions inside the fresh,blood purified,dehydrated,and coagulated tissue models have been investigated by using the Monte Carlo modeling of photon transport in multilayered tissues simulation code.

关键词： optical properties Dehydration coagulation integrating sphere IAD

Rapid Dehydration of grape berries dampens the post-ripening transcriptomic program and the metabolite profile evolution

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Horticulture Research 2020年第1期7卷 1016-1030页

作者： Sara Zenoni Alessandra Amato Erica D’Incà Flavia Guzzo Giovanni Battista Tornielli Department of Biotechnology University of VeronaStrada Le Grazie 1537134 VeronaItaly

The postharvest Dehydration of grape berries allows the concentration of sugars and other solutes and promotes the synthesis of metabolites and aroma compounds unique to high-quality raisin wines such as the passito wines made in Italy.These dynamic changes are dependent on environmental parameters such as temperature and relative humidity,as well as endogenous factors such as berry morphology and genotype,but the contribution of each variable is not well understood.Here,we compared berries subjected to natural or accelerated Dehydration,the latter driven by forced air flow.We followed the evolution of transcript and metabolite profiles and found that accelerated Dehydration clearly dampened the natural transcriptomic and metabolomic programs of postharvest berries.We found that slow Dehydration over a prolonged duration is necessary to induce gene expression and metabolite accumulation associated with the final quality traits of dehydrated berries.The accumulation of key metabolites(particularly stilbenoids)during postharvest Dehydration is inhibited by rapid Dehydration conditions that shorten the berry life time.

关键词： flow Dehydration latter

Dehydration at subduction zones and the geochemistry of slab fluids

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Science China Earth Sciences 2020年第12期63卷 1925-1937页

作者： Wancai Li Huaiwei Ni CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China CAS Center for Excellence in Comparative Planetology Hefei230026China

Subducting oceanic slabs undergo metamorphic Dehydration with the increase of temperature and pressure during subduction.Dehydration is an essential step for element recycling,and slab fluids are critical agents for mediating slab-mantle interaction.Dehydration is mainly controlled by the thermal structure of subduction zones and the stability of hydrous minerals.At fore-arc depths,slab Dehydration produces aqueous fluid with dissolved salts such as NaCl.As subduction proceeds deeper,the content of silicate components increases.At sub-arc and post-arc depths,a hydrous silicate melt is likely to form,or a supercritical fluid could arise from complete miscibility between silicates and H_(2)O.The partitioning of elements between slab fluid and the residual solid rock is controlled by the type of fluid,and generally it is the supercritical fluid that is the most capable of mobilizing trace elements,being an effective carrier even for high field strength elements.Understanding the chemistry of slab fluids relies on sophisticated integration of experiments,theoretical computation and investigation of natural rock samples.This contribution focuses on the content and speciation of key volatiles,including carbon,nitrogen and sulfur,in slab fluids as well as important fluid properties such as oxygen fugacity and acidity.The properties of slab fluids show complicated variation under the control of mineral assemblages and T-P conditions.Slab fluids at great depths of subductions have been inferred to be modestly alkaline and not necessarily very oxidizing as often assumed.Further progress in the research of slab Dehydration and the chemistry and properties of slab fluids demands urgently the development of innovative experimental and computational technology including in situ analytical methods at high T-P.

关键词： Subduction zone Dehydration Slab fluids Volatiles Oxygen fugacity Acidity

Predictors of Dehydration and acute renal failure in patients with diverting loop ileostomy creation after colorectal surgery

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World Journal of Clinical Cases 2019年第14期7卷 1805-1813页

作者： Omar Vergara-Fernández Mario Trejo-Avila Oscar Santes Danilo Solórzano-Vicu?a Noel Salgado-Nesme Department of Colorectal Surgery Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán"

BACKGROUND Despite the potential benefits of fecal diversion after low pelvic anastomosis in colorectal surgery, diverting loop ileostomy construction is related to significant rates of complications. AIM To determine potential predictors of high output related complications in patients with diverting loop ileostomy creation after colorectal surgery. METHODS Patients who underwent open and laparoscopic colorectal surgery requiring a diverting loop ileostomy from January 2010 to March 2018 were retrospectively analyzed. We included patients older than 18 years, who underwent colorectal surgery with primary low pelvic anastomosis, and with the creation of a diverting loop ileostomy, at elective or emergency settings for the treatment of benign or malignant conditions. Univariate and multivariate logistic regression analysis was used to determine the effect of the potential predictors on the rate of high output related complications. The high output related complications were Dehydration and acute renal failure that required visits to the emergency department and hospitalizations. RESULTS Of the 102 patients included in the study, 23.5%(n = 24) suffered high output related complications. In this group of patients at least one visit to the emergency department (mean 1.6), and at least one readmission to the hospital was needed. The factors associated with high-output ileostomy, in the univariate analysis, were: urgent surgical intervention (OR = 2.6;P = 0.047), the development of postoperative complications (OR = 3;P = 0.024), have ulcerative colitis (OR = 4.8;P = 0.017), use of steroids (OR = 4.3;P = 0.010), mean output at discharge greater than 1000 mL/24 h (OR = 3.2;P = 0.016), and use of loperamide at discharge (OR = 2.8;P = 0.032). Multivariate logistic regression analysis identified two independent risk factors for high output related complications: ulcerative colitis [OR = 7.6 (95%CI: 1.81-31.95);P = 0.006], and ileostomy output at discharge ≥ 1000 mL/24 h [OR = 3.3 (1.18-9.37);P = 0.023]. CONCLUSION In our st

关键词： Loop ileostomy High-output ileostomy Loop ileostomy complications Dehydration Colorectal surgery

Recent advances in acid-resistant zeolite T membranes for Dehydration of organics

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Chinese Journal of Chemical Engineering 2019年第6期27卷 1449-1457页

作者： Yiwei Luo Waseem Raza Jianhua Yang Liangqing Li Ying Lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China Collaborative Innovation Center of Fine Chemical and Materials Technology School of Chemistry and Chemical EngineeringHuangshan UniversityHuangshan 245041China

Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh conditions.Development of durable and high separation performance membranes with lower fabrication and operation cost are highly demanded for industrial applications. Zeolite T membrane possesses good acid-resistance with excellent hydrophilic properties as compared to NaA zeolite membrane and can be extended to industrial organic Dehydrations under an acidic environment. In the present review the research advances in development of zeolite T membranes for the Dehydration of organic mixtures in acidic conditions are summarized. Especially the low temperature synthesis, and epitaxial growth of the zeolite membrane with high performance are well addressed, besides emphasis is particularly placed on ensemble synthesis of hollow fiber zeolite T membrane module and its future prospects for industrial separations.

关键词： Dehydration of organics Epitaxial growth Zeolite T membrane Membrane pervaporation

Regulation of rose petal Dehydration tolerance and senescence by RhNAP transcription factor via the modulation of cytokinin catabolism

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Molecular Horticulture 2021年第1期1卷 45-59页

作者： Jing Zou Peitao Lü Liwei Jiang Kun Liu Tao Zhang Jin Chen Yi Yao Yusen Cui Junping Gao Changqing Zhang Department of Ornamental Horticulture China Agricultural UniversityBeijing 100193China College of Horticulture FAFU-UCR Joint Center for Horticultural Biology and MetabolomicsHaixia Institute of Science and TechnologyFujian Agriculture and Forestry UniversityFuzhou 350002China

Petals and leaves share common evolutionary origins but have different phenotypic characteristics,such as the absence of stomata in the petals of most angiosperm species.Plant NAC transcription factor,NAP,is involved in ABA responses and regulates senescence-associated genes,and especially those that affect stomatal movement.However,the regulatory mechanisms and significance of NAP action in senescing astomatous petals is unclear.A major limiting factor is failure of flower opening and accelerated senescence.Our goal is to understand the finely regulatory mechanism of Dehydration tolerance and aging in rose flowers.We functionally characterized RhNAP,an AtNAP-like transcription factor gene that is induced by Dehydration and aging in astomatous rose petals.Cytokinins(CKs)are known to delay petal senescence and we found that a cytokinin oxidase/dehydrogenase gene 6(RhCKX6)shares similar expression patterns with RhNAP.Silencing of RhNAP or RhCKX6 expression in rose petals by virus induced gene silencing markedly reduced petal Dehydration tolerance and delayed petal senescence.Endogenous CK levels in RhNAP-or RhCKX6-silenced petals were significantly higher than those of the control.Moreover,RhCKX6 expression was reduced in RhNAP-silenced petals.This suggests that the expression of RhCKX6 is regulated by RhNAP.Yeast one-hybrid experiments and electrophoresis mobility shift assays showed that RhNAP binds to the RhCKX6 promoter in heterologous in vivo system and in vitro,respectively.Furthermore,the expression of putative signal transduction and downstream genes of ABA-signaling pathways were also reduced due to the repression of PP2C homolog genes by RhNAP in rose petals.Taken together,our study indicates that the RhNAP/RhCKX6 interaction represents a regulatory step enhancing Dehydration tolerance in young rose petals and accelerating senescence in mature petals in a stomata-independent manner.

关键词： Rosa hybrida RhNAP RhCKX6 Dehydration Petal senescence Cytokinins