• Title/Summary/Keyword: dehydration reaction

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Two Clinical Cases of Feline Hemoplasmosis in Korea

  • Kim, Young Ju;Bae, Hyeona;Shin, Sun Woo;Cho, ARom;Jeon, Yeseul;Hwang, Tae-Sung;Jung, Dong-In;Kim, Dae Young;Kang, Jun-Gu;Yu, DoHyeon
    • Parasites, Hosts and Diseases
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    • v.60 no.2
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    • pp.127-131
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    • 2022
  • Feline hemotropic mycoplasmosis (hemoplasmosis) is an infection of the red blood cells caused by the Mycoplasma haemofelis (Mhf), Candidatus Mycoplasma haemominutum (CMhm), and Candidatus Mycoplasma turicensis (CMt). The existence of Mhf, CMhm, and CMt has been demonstrated in feral cats in Korea using molecular methods, but no clinical cases have yet been reported. This study reports 2 clinical cases of hemotropic mycoplasmosis caused by CMhm and CMt in 2 anemic cats. The first case was a client-owned intact female domestic shorthair cat that presented with fever, pale mucous membranes, and normocytic normochromic non-regenerative anemia. Prior to referral, an immunosuppressive prednisolone dose was administered at the local veterinary clinic for 1 month. The cat was diagnosed with high-grade alimentary lymphoma. Organisms were found on the surface of the red blood cells on blood smear examination. The second case was of a rescued cat that presented with dehydration and fever. The cat had normocytic normochromic non-regenerative anemia. Necropsy revealed concurrent feline infectious peritonitis. Polymerase chain reaction assay targeting 16S rRNA revealed CMhm infection in case 1 and dual infection of CMhm and CMt in case 2. Normocytic normochromic non-regenerative anemia was observed in both cats before and during the management of the systemic inflammation. This is the first clinical case report in Korea to demonstrate CMhm and CMt infections in symptomatic cats.

Formation of Al2O2 supported Ni2P based 3D catalyst for atmospheric deoxygenation of rubberwood sawdust

  • Pranshu Shrivastava
    • Advances in Energy Research
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    • v.8 no.4
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    • pp.223-231
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    • 2022
  • An ex-situ gravitational fixed bed pyrolysis reactor was used over Al2O3 supported Ni2P based catalyst with various Ni/P molar ratios (0.5-2.0) and constant nickel loading of 5.37 mmol/g Al2O3 to determine the hydrodeoxygenation of rubberwood sawdust (RWS) at atmospheric pressure. The 3D catalysts formed were characterized structurally as well as acidic properties were determined by hydrogen-temperature programmed reduction (TPR). The Ni2P phase formed completely on Al2O3 for 1.5 Ni/P ratio, although lesser crystallite sizes of Ni2P were seen at Ni/P ratios less than 1.5. Additionally, it was shown that when nickel loading level increased, acidity increased and specific surface area dropped, probably because nickel phosphate is not easily converted to Ni2P. When Ni/P ratio was 1.5, Ni2P phase fully formed on Al2O3. The catalytic activity was explained in terms of impacts of reaction temperature and Ni/P molar ratio. At relatively high temperature of 450℃, the high-value deoxygenated produce was predominantly composed of n-alkanes. Based on the findings, it was suggested that hydrogenolysis, hydrodeoxygenation, dehydration, decarbonylation, and hydrogenation are all part of mechanism underlying hydrotreatment of RWS. In conclusion, the synthesized Ni2P/ Al2O3 catalyst was capable of deoxygenating RWS with ease at atmospheric pressure, primarily resulting in long chained (C9-C24) hydrocarbons and acetic acid.

Enhancement of High-Temperature Catalytic Reactions Using Membranes (분리막을 이용한 고온 촉매 반응 효율 향상)

  • Eun-Young Kim;Myeong-Hun Hyeon;Su-Young Moon
    • Membrane Journal
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    • v.33 no.6
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    • pp.305-314
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    • 2023
  • Various methods for removing by-products from chemical reactions are being studied to improve yield of catalytic reaction. Since the water is predominantly generated as a by-product in industrially significant reactions, it is necessary to develop the technology that can reliably remove water over a wide range of temperatures. Although several strategies using absorbents and additional dehydration reactions, have been proposed, they have limitations due to the issues such as additional energy and time consuming steps and sustainability of conversion. Membrane technology, which offers advantages such as easy operation, installation, and low maintenance costs, proves to be a promising approach for enhancing the efficiency of catalysts in various catalytic reactions. Therefore, this review discusses the removal of by-products using membranes and the associated benefits in this context.

Oral Administration of Alcohol-Tolerant Lactic Acid Bacteria Alleviates Blood Alcohol Concentration and Ethanol-Induced Liver Damage in Rodents

  • Misun Yun;Hee Eun Jo;Namhee Kim;Hyo Kyeong Park;Young Seo Jang;Ga Hee Choi;Ha Eun Jo;Jeong Hyun Seo;Ji Ye Mok;Sang Min Park;Hak-Jong Choi
    • Journal of Microbiology and Biotechnology
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    • v.34 no.4
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    • pp.838-845
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    • 2024
  • Excessive alcohol consumption can have serious negative consequences on health, including addiction, liver damage, and other long-term effects. The causes of hangovers include dehydration, alcohol and alcohol metabolite toxicity, and nutrient deficiency due to absorption disorders. Additionally, alcohol consumption can slow reaction times, making it more difficult to rapidly respond to situations that require quick thinking. Exposure to a large amount of ethanol can also negatively affect a person's righting reflex and balance. In this study, we evaluated the potential of lactic acid bacteria (LAB) to alleviate alcohol-induced effects and behavioral responses. Two LAB strains isolated from kimchi, Levilactobacillus brevis WiKim0168 and Leuconostoc mesenteroides WiKim0172, were selected for their ethanol tolerance and potential to alleviate hangover symptoms. Enzyme activity assays for alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) were then conducted to evaluate the role of these bacteria in alcohol metabolism. Through in vitro and in vivo studies, these strains were assessed for their ability to reduce blood alcohol concentrations and protect against alcohol-induced liver damage. The results indicated that these LAB strains possess significant ethanol tolerance and elevate ADH and ALDH activities. LAB administration remarkably reduced blood alcohol levels in rats after excessive alcohol consumption. Moreover, the LAB strains showed hepatoprotective effects and enhanced behavioral outcomes, highlighting their potential as probiotics for counteracting the adverse effects of alcohol consumption. These findings support the development of functional foods incorporating LAB strains that can mediate behavioral improvements following alcohol intake.

The High temperature stability limit of talc, $Mg_3Si_4O_{10}(OH)_2$ (활석 $Mg_3Si_4O_{10}(OH)_2$의 고온 안정영역에 관한 실험적 연구)

  • 조동수;김형식
    • The Journal of the Petrological Society of Korea
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    • v.6 no.2
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    • pp.123-132
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    • 1997
  • In the system $MgO-SiO_2-H_2O$, Talc[$Mg_3Si_4O_{10}(OH)_2$] has been synthesized hydrothermally at 200 MPa, $600^{\circ}C$ from the oxide mixture of the bulk composition of talc. The oxide mixture of the bulk composition of anthophyllite$[Mg_7Si_8O_{22}(OH)2]$ converted to talc, enstatite $(MgSiO_3)$, quartz at 200 MPa, $750^{\circ}C$ with excess of $H_2O$. In low to medium pressure metramorphism, enstatite-talc assemblage is metastable relative to anthophyllite with the reaction talc + 4 enstatite=anthophyllite (Greenwood, 1963). The high temperature stability of talc is bounded with the dehydration reaction to anthophyllite rather than that to enstatite(Greenwood, 1963; Chernosky et al., 1985). Therefore our experiment result assemblage, enstatite-talc-quatz at 200 MPa, $750^{\circ}C$ from oxide mixture of bulk compostion of anthophyllite is metastable assemblage. The hydrothermal experiment performed at 41 to 243 MPa, 680 to $760^{\circ}C$ with the starting material composed of synthetic talc, enstatite and quartz. Talc or enstatite grows during the runs and no extra phases including anthophyllite nucleated. Based on the increase or decrease of the each phase from run products, one of the possible reactions is talc=3 enstatite+quartz+H_2O$. The reversal bracket of the reaction is 699 to $700^{\circ}C$ at 100 MPa. Talc is stable up to $740^{\circ}C$ at 200 MPa and enstatite grow at $680^{\circ}C$, 40 MPa and at $760^{\circ}C$, 250 MPa. Though the high temperature limit of talc around 200 MPa is bounded thermodynamically by the reaction, 7 talc=3 anthophyllite+4 quartz+4 H_2O$, talc persisted throughout the previous reaction up to the reaction, talc=3 enstatite+quartz+$H_2O$.

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Characterization of Synthetic Na-beidellite (합성 Na-베이델라이트의 광물특성)

  • Ryu Gyoung-Won;Chae Soo-Chun;Bae In-Kook;Choi Sang-Hoon;Jang Young-Nam
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.2
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    • pp.109-115
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    • 2005
  • Beidellite, a member of the smectite group, was synthesized hydrothermally from dickite. Physical and chemical properties of the synthetic Na-beidellite were characterized by the analytical methods of XRD, IR, TG, DTA, EDS, XRF and ICP. The result of Greene-Kelly test indicates that the synthesized smectite is Na-beidellite. IR spectrum of synthesized beidellite exhibited Al-O-H bending vibration at $818\;cm^{-1}\;and\;770\;cm^{-1}$ which was observed particularly in pure beidellite. TGA analysis revealed that the synthesized Na-beidellite comprises $16\;wt\%$ of water. DTA curve showed an endothermic peak at $117^{\circ}C$ due to dehydration reaction and peaks at $482^{\circ}C$ and $685^{\circ}C$ due to dehydroxylation reaction. The clay mineral was transformed to mullite and cristobalite at the temperature of $1028^{\circ}C$. The CEC value, Methylene Blue test and swelling capacity was determined to be $116\~118\;cmol/kg,\;84\~91\%,\;29\~32\;mL/2g$, respectively. The chemical composition of the synthesized phase was identified as $Na_{0.5}Al_{2.5}Si_{3.5}O_{10}(OH)_2$ from EDS and XRF analyses.

Direct Conversion for the Production of 5-HMF from Cellulose over Immobilized Acidic Ionic Liquid Catalyst with Metal Chloride (고정화 산성 이온성 액체 촉매와 금속염화물 촉매를 이용한 셀룰로우스의 5-HMF로의 직접 전환 연구)

  • Park, Yong Beom;Choi, Jae Hyung;Lim, Han-Kwon;Woo, Hee-Chul
    • Clean Technology
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    • v.20 no.2
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    • pp.108-115
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    • 2014
  • Various metal chlorides and acid catalysts in ionic liquid solvent were investigated to directly convert cellulose into 5-hydroxymethylfurfural (5-HMF). Metal chlorides containing Sn(II), Zn(II), Al(III), Fe(III), Cu(II), and Cr(III) were used and acidic ionic liquid immobilized on silica gel as an acid catalyst and commercial acid catalysts (sulfuric acid, chloric acid, Amberlyst-15,DOWEX50x8) were used for comparison studies. The acid strength and amount of acid catalysts were probed with Hammett indicator. The selectivity and yield of 5-HMF were determined with reaction temperature, reaction time and catalyst ratio. A catalyst containing $CrCl_3-6H_2O$ and $SiO_2-[ASBI]HSO_4$ showed the highest selectivity and it was found that this catalyst had higher activity than commercial solid acid catalysts such as Amberlyst-15 and DOWEX50x8. The selectivity of 5-HMF appeared to be mainly dependent on the acid strength and catalyst ratio, it was found that levulinic acid was produced from 5-HMF by rehydration.

Synthesis and stability relations of zoisite $Ca_2$Al$_3$Si$_3$O$_{12}$(OH) at 2-4 kbar (조이사이트 $Ca_2$Al$_3$Si$_3$O$_{12}$(OH)의 합성 및 2-4 kbar에서의 안정관계)

  • Kim Hyung Shik;Park Chan Soo
    • The Journal of the Petrological Society of Korea
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    • v.1 no.1
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    • pp.42-48
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    • 1992
  • The equilibrium pressure-temperature curve of the reaction: 6 Ca$_2$Al$_3$(OH)Si$_3$O$_{12}$=6 CaAl$_2$Si$_2$O$_{8}$+2 Ca$_3$Al$_2$Si$_3$O$_{12}$+Al$_2$O$_3$+3 H$_2$O zoisite anorthite grossularite corundum was experimentally determined using both externally and internally heated pressure vessels in the pressure range of 2-4 kbar. Synthetic zoisite, anorthite, grossularite and corundum were used as starting materials. Starting materials were synthesized at 13-16 kbar using the piston-cylinder apparatus. The dehydration temperature of zoisite at 2 kbar is 550${\pm}$12$^{\circ}C$ and at 4 kbar is 575${\pm}$20$^{\circ}C$. Low thermal stability of synthetic zoisite relative to natural zoisite at 4 kbar is attributed to the structural disorder of synthetic anorthite.

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Development of Light-weight Fire Protection Materials Using Fly Ash and Light-weight Aggregate (플라이애시 및 경량골재를 활용한 경량 내화성 마감재료 개발)

  • Song, Hun;Chu, Yong-Sik;Lee, Jong-Kyu;Lee, Sea-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.4
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    • pp.95-102
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    • 2012
  • The serious issue of tall building is to ensure the fire resistance of high strength concrete. Therefore, Solving methods are required to control the explosive spalling. The fire resistant finishing method is installed by applying a fire resistant material as a light-weight material to structural steel and concrete surface. This method can reduce the temperature increase of the reinforcement embedded in structural steel and concrete at high temperature due to the installation thickness control. This study is interested in identifying the effectiveness of light-weight fire protection material compounds including the inorganic admixture such as fly ash, meta-kaolin and light-weight aggregate as the fire resistant finishing materials through the analysis of fire resistance and components properties at high temperature. Also, this paper is concerned with change in microstructure and dehydration of the light-weight fire protection materials at high temperatures. The testing methods of fire protection materials in high temperature properties are make use of SEM and XRD. The study results show that the light-weight fire resistant finishing material composed of fly ash, meta-kaolin and light-weight aggregate has the thermal stability of the slight decrease of compressive strength at high temperature. These thermal stability is caused by the ceramic binding capacity induced by alkali activation reaction by the reason of the thermal analysis result not showing the decomposition of calcium hydrate. Developed light-weight fire protection materials showed good stability in high Temperatures. Thus, the results indicate that it is possible to fireproof panels, fire protection of materials.

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In-situ Phase Transition Study of Minerals using Micro-focusing Rotating-anode X-ray and 2-Dimensional Area Detector (집속 회전형 X-선원과 이차원 검출기를 이용한 광물의 실시간 상전이 연구)

  • Seoung, Dong-Hoon;Lee, Yong-Moon;Lee, Yong-Jae
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.79-88
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    • 2012
  • The increased brightness and focused X-ray beams now available from laboratory X-ray sources facilitates a variety of powder diffraction experiments not practical using conventional in-house sources. Furthermore, the increased availability of 2-dimensional area detectors, along with implementation of improved software and customized sample environmental cells, makes possible new classes of in-situ and time-resolved diffraction experiments. These include phase transitions under variable pressure- and temperature conditions and ion-exchange reactions. Examples of in-situ and time-resolved studies which are presented here include: (1) time-resolved data to evaluate the kinetics and mechanism of ion exchange in mineral natrolite; (2) in-situ dehydration and thermal expansion behaviors of ion-exchanged natrolite; and (3) observations of the phases forming under controlled hydrostatic pressure conditions in ion-exchanged natrolite. Both the quantity and quality of the in-situ diffraction data are such to allow evaluation of the reaction pathway and Rietveld analysis on selected dataset. These laboratory-based in-situ studies will increase the predictability of the follow-up experiments at more specialized beamlines at the synchrotron.