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Production of octyl levulinate biolubricant over modified H-ZSM-5:Optimization by response surface methodology 被引量:1
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作者 Kakasaheb Y.Nandiwale Sunil K.Yadava Vijay V.Bokade 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第4期535-541,共7页
The present study highlighted the use of modified H-ZSM-5 (Meso-HZ-5) as heterogeneous catalyst for the synthesis of octyl levulinate biolubricant by catalytic esterification of biomass derived renewable levulinic a... The present study highlighted the use of modified H-ZSM-5 (Meso-HZ-5) as heterogeneous catalyst for the synthesis of octyl levulinate biolubricant by catalytic esterification of biomass derived renewable levulinic acid (LA) with n-octanol. The process variables such as catalyst loading (X1), n-octanol to LA molar ratio (X2) and reaction temperature (X3) were optimized through response surface methodology (RSM), using Box-Behnken model. Analysis of variance was performed to determine the adequacy and significance of the quadratic model. The yield of octyl levulinate was obtained to be 99% at optimum process parameters. The developed quadratic model was found to be adequate and statistically accurate with correlation value (R2) of 0.9971 to predict the yield of octyl levulinate biolubricant. The study was also extended on the validation of theoretical and experimental data, including catalyst reusability. 展开更多
关键词 biolubricant ESTERIFICATION H-ZSM-5 levulinic acid octyl levulinate response surface methodology
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Synthesis and Characterization of 2-cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester 被引量:1
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作者 翁睿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期292-294,共3页
2-Cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental resul... 2-Cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental results show that the yield of products can be 89% when the molar ratio of perfluorinated octyl sulfonamide to ketene dimer is 1 : 1.1 and the reaction lasts about four hours at 80 ℃. The structure of the product was characterized by FTIR and ^1HNMR. The product can dissolve in polar solvents such as NMP, DMAC, THF, DMSO, CHCl3, and 10% weight-loss temperature measured by TGA is 202℃. 展开更多
关键词 keto ester N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide thermal performance
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Flotation mechanism of octylic hydroxamic acid on diaspore 被引量:3
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作者 LIU Sanjun QIN Wenqing +1 位作者 PENG Tiefeng HU Yuehua 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2013年第2期191-194,共4页
Bauxite resources are widely spread in the earth. However, the effective utilization of this mineral is still under infant. The conventional collector for diaspore mineral is oleic acid. It has three main drawbacks wh... Bauxite resources are widely spread in the earth. However, the effective utilization of this mineral is still under infant. The conventional collector for diaspore mineral is oleic acid. It has three main drawbacks which are highly insoluble, large dosages in bauxite flotation, and low selectivity, which hinder its application in industry. In this research, octylic hydroxamic acid was synthesized, and its collecting ability toward two major minerals in bauxite-diaspore and kaolinite was investigated. The collecting power of various reagents for diaspore are shown as follows: oleic acid<octylic hydroxamic acid; while the collecting power for kaolinite was like this: octylic hydroxamic acid<oleic acid. It is shown that octylic hydroxamic acid has the capability of high collectivity and good selectivity. The optimum pH was determined to be 8 9. Zeta potential test revealed that the anionic collectors-octylic hydroxamic acid and oleic acid had been adsorbed on the surface of diaspore and kaolinite, meanwhile the adsorption for diaspore was more remarkable. By the adsorptive capability and IR tests, the adsorption of octylic hydroxamic acid on diaspore was determined to be a process of chemical absorption, which was greater than that of oleic acid. 展开更多
关键词 一水硬铝石 异羟肟酸 浮选机理 辛酸 铝土矿资源 吸附能力 硬水铝石 电位测试
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Extraction Separation of Scandium,Iron and Lutetium with Isopropyl Phosphonic Acid Mono(1-hexyl-4-ethyl)OctylEster 被引量:1
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作者 孙静 李德谦 叶伟贞 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第1期5-9,共5页
The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation betwee... The extraction and stripping of scandium from its sulfate solutions by isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester (PT-2, HL) diluted with n-hexane are reported. A high efficiency of separation between scandium, iron and lutetium can be achieved by controlling aqueous acidity. Different mechanisms of Sc3+ with PT-2 in various acid range have been proposed.At lower aqueous acidity, it is a cation exchange reaction, while at higher acidity. a solvation reaction was ascertained. Its IR and NMR spectra have been discussed. The effect of temperature on extraction of Sc3+ was observed and thermodynamic functions were calculated. 展开更多
关键词 Isopropyl phosphonic acid mono (1-hexyl-4-ethyl) octyl ester. Extraction separation Scandium Iron LUTETIUM
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Extraction of Zr(IV) from hydrochloric acid with tri-octyl amine and Cyanex 921 in kerosene 被引量:5
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作者 Bhikari Charan Bhatta Nandita Panda Sujata Mishra 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第9期823-828,共6页
This article reports the extraction of zirconium (IV) from aqueous HC1 solution by tri-octyl amine (TOA), Cyanex 921, and their binary mixture using kerosene as the diluent. The effect of some parameters on the ex... This article reports the extraction of zirconium (IV) from aqueous HC1 solution by tri-octyl amine (TOA), Cyanex 921, and their binary mixture using kerosene as the diluent. The effect of some parameters on the extraction of Zr(IV) was investigated such as equilibration time, aqueous phase acidity, extractant molarity, chloride ion concentration, nature of diluents, and temperature. The extraction of Zr(IV) was found to be 99% from 7.5 M HC1 using the mixture of extractants containing 0.1 M TOA and 0.02 M Cyanex 921 in kerosene. Kerosene was found to be the effective diluent for the extraction of Zr(IV) with the binary mixture of TOA and Cyanex 921. The positive enthalpy change and positive entropy change in the binary extraction system show the endothermic process with an increase in entropy. Stripping of Zr(IV) from the loaded organic phase containing the mixture of TOA (0.1 M) and Cyanex 921 (0.02 M) indicates that HNO3 and Na2CO3 are the best stripping agents. 展开更多
关键词 zirconium solvent extraction hydrochloric acid tri-octyl amine Cyanex 921 KEROSENE
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Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant 被引量:1
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作者 Song-Ping Wu 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期425-430,共6页
Solvent extraction of palladium (Ⅱ) from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one (OIT)/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.9... Solvent extraction of palladium (Ⅱ) from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one (OIT)/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium (Ⅱ) could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium (Ⅱ) from the loaded organic phase was achieved with 0.5 mol·L^-1 (NH2)2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra. 展开更多
关键词 Solvent extraction PALLADIUM 2-n-octyl-4-isothiazolin-3-one OIT STRIPPING
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2-Octyl Cyanoacrylate Skin Adhesive for Topical Skin Incision Closure in Female Pelvic Surgery
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作者 Rebecca L. James Marilyn Alejandro-Rodriquez +1 位作者 Elba Adriana Perez Jeffrey Mangel 《Open Journal of Obstetrics and Gynecology》 2015年第5期280-285,共6页
Background: 2-octyl cyanoacrylate (2OCA) high viscosity tissue adhesive (Medline Industries, Inc., Mundelein, IL) is a liquid topical skin adhesive. 2OCA offers the same design features and clinical utility in terms o... Background: 2-octyl cyanoacrylate (2OCA) high viscosity tissue adhesive (Medline Industries, Inc., Mundelein, IL) is a liquid topical skin adhesive. 2OCA offers the same design features and clinical utility in terms of flexibility, strength, and low complication rate as the commercially available 2OCA tissue adhesives. Additionally, 2OCA features high viscosity allowing for better control during the application process, polymerization without the use of an external activator, and a distinctive violet color for ease of application visualization. Objective: The aim of this prospective case series is to descriptively report clinical data with the application of 2OCA as a topical incision closure system in female pelvic surgery. The primary outcomes included: incisional pain, incisional dehiscence, and post-operative bleeding. The secondary outcome included drying times of the adhesive with regard to incision length. Methods: A prospective open-label observational case series study was conducted to evaluate the use of 2OCA in surgical wound closure of the topical skin in adult patients undergoing gynecologic surgical procedures. A total of 50 adult women undergoing gynecologic surgery were enrolled. 2OCA was applied only by surgeons who had undergone product training to the incisions in a standardized, protocol-defined fashion. Drying times for the adhesive and photography were recorded intraoperatively. Post treatment follow-up was conducted with queries of pain level, incisional dehiscence, and incisional bleeding immediately post-operatively, 48 hours, 5 - 10 days and 14 days post-treatment. Adverse events were documented. Results: 2OCA was applied to a total of 154 incisions from the 50 patients enrolled to the study. The procedures included: 16 laparoscopic total hysterectomies, 4 diagnostic laparoscopies, 2 laparoscopic myomectomies, 2 laparoscopic bilateral or unilateral salpingo-oophorectomies, 5 total robotic-assisted laparoscopic surgeries (2 total hysterectomies, 1 supracervical hysterectomy, 1 sacrocolpopexy, and one excision of endometriosis), 7 sacral neuromodulation procedures, and 18 midurethral slings. The overall rate of incisional dehiscence was 3% (4/154). The rate of reported incisional bleeding was 3% (4/154). There was 1 incisional infection. The pain reports based on a 10-point scale had a mean of 4.96 immediately post-operatively, which decreased to a mean score < 1 (0.2) by post-op day (POD) 14. The mean drying times for the various lengths of incisions included the following: 1.28 minutes for incisions ≤ 5 mm, 1.53 minutes for 6 - 8 mm, 1.66 minutes for 10 mm - 20 mm, and 1.57 minutes for the 40 - 50 mm incisions. In 23% (36/154) of incisions 2OCA was the sole method of skin closure. Conclusion: This study demonstrates that 2OCA is safe to use in gynecologic surgical incisions with low rates of post-operative incisional bleeding and incisional dehiscence. Post-operative reports of pain maintained expected levels for recovery. 2OCA is a practical alternative or augmentation to traditional suture closure of skin incisions at the time of gynecologic surgery. 展开更多
关键词 FEMALE Pelvic SURGERY Gynecologic SURGERY octyl CYANOACRYLATE Surgical Incision SKIN CLOSURE
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The Transient Time-Resolved Absorption Spectra of 1-Naphthylacetic Acid
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作者 Li, W Tung, CH Ye, JP 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第3期261-262,共2页
The transient absorption spectra of 1-naphthylacetic acid in tetrahydrofuran have been obtained by laser flash photolysis technique. The transient species bands are at 509, 535 and 553 nm. These peak intensities incre... The transient absorption spectra of 1-naphthylacetic acid in tetrahydrofuran have been obtained by laser flash photolysis technique. The transient species bands are at 509, 535 and 553 nm. These peak intensities increase in the maximum values at 10.4 mu s. 展开更多
关键词 transient spectra laser chemistry 1-naphthylacetic acid
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Crystal Structure of a Novel Sandwich Inclusion Complex of β-Cyclodextrin with α-Naphthylacetic Acid
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作者 WANG En-ju CHEN Guang-ying HAN Chang-ri 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期730-733,共4页
A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two... A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [(C42H70O35)2·(C12H10O2)·(C2H5OH)2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol. 展开更多
关键词 Β-CYCLODEXTRIN α-naphthylacetic acid Inclusion complex Sandwich complex Competitive inclusion
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Synthesis and Properties of Poly (n-Octyl Acrylate) with Uniform Polystyrene Grafts
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作者 廖桂英 姜胜斌 《Journal of China University of Geosciences》 SCIE CSCD 2007年第2期153-157,共5页
Poly (n-octyl acrylate) with uniform polystyrene grafts (POA-g-PS) was obtained by radical copolymerization of n-octyl acrylate (OA) with PS macromer, in solution. The reactivity ratio and effects of copolymeriz... Poly (n-octyl acrylate) with uniform polystyrene grafts (POA-g-PS) was obtained by radical copolymerization of n-octyl acrylate (OA) with PS macromer, in solution. The reactivity ratio and effects of copolymerization conditions on grafting efficiency were studied. The crude products were purified by extraction with cyclohexane and n-butanol successively. POA-g-PS exhibited a very good compatibilizing effect on the acrylic rubber/polystyrene blends. 2﹪-3﹪ of the graft copolymer was enough for enhancing the tensile strength of the blends. DSC and SEM demonstrated the enhancement of compatibility in the presence of the graft copolymer. 展开更多
关键词 graft copolymer PS macromer n-octyl acrylate blend COMPATIBILIZER
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Extraction of Gold by Di(2-ethylhexyl)Sulfoxide and N-Octyl Sulfoxide
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作者 Lu Zhong’e, Que Haoquan, Liu Guoxing, Wang Hanzhang and Zhu Qinhua (Department of Chemistry, Suzhou University, Suzhou) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第3期231-236,共6页
A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,... A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,M.using petroleum sulfoxide and n-dioctyl sulfoxide(DOSO) as an extractant respectively. 展开更多
关键词 EXTRACTION Di(2-ethyl hexyl)sulfoxide N-octyl sulfoxide GOLD
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Definition of Planarian Mortality in an Acute Toxicity Test:A Case Study on Dugesia japonica Exposed to 1-Octyl-3-methylimidazolium Bromide
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作者 Zhang Hecai Liu Tongyi +3 位作者 Liu Yanfang Zhang Jie Wang Zhige Chen Guangwen 《生态毒理学报》 CAS CSCD 北大核心 2016年第6期291-295,共5页
In order to define the mortality criteria of planarian objectively,a case study of Dugesia japonica exposed to 1-octyl-3-methylimidazolium bromide([C8mim]Br)was performed followed by a recovery culture.The results sho... In order to define the mortality criteria of planarian objectively,a case study of Dugesia japonica exposed to 1-octyl-3-methylimidazolium bromide([C8mim]Br)was performed followed by a recovery culture.The results showed that defining planarian mortality in light of its body disintegration was appropriate.If the disintegrated tissue of a planarian was more than 1/4 of its body length,it would completely degenerate.However,a planarian would regenerate the lost tissue and return to normal after a few days’recovery culture if the disintegrated part was less than 1/4 of body length.Therefore,we propose to use body disintegration as the endpoint of planarian mortality,i.e.,1/4 body length degenerated is the critical threshold of mortality and survival of planarians when exposed to toxicants.This criterion could be adapted in the standardization of testing protocols and comparability of acute toxicity test or other toxicological research using planarian as the test animal. 展开更多
关键词 生态环境 毒理学 环境保护 生态保护
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Action mechanism of octylic hydroxamic acid on diaspore
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作者 Liu Sanjun Qin Wenqing Hu Yuehua 《Engineering Sciences》 2012年第1期76-79,共4页
The conventional collector for diaspore mineral is oleic acid,which is highly insoluble and must be used in high dosage in bauxite flotation,that is the great drawback of oleic acid in use.Octylic hydroxamic acid was ... The conventional collector for diaspore mineral is oleic acid,which is highly insoluble and must be used in high dosage in bauxite flotation,that is the great drawback of oleic acid in use.Octylic hydroxamic acid was synthesized,and its collecting ability to certain minerals in bauxite:diaspore and kaolinite were studied.The collecting power of various reagents to diaspore in an incremental sequence was shown as follows:oleic acid<octylic hydroxamic acid,while the incremental sequence of the collecting power to kaolinite was like this:octylic hydroxamic acid < oleic acid.It could be seen that octylic hydroxamic acid had the capability of high collectivity and good selectivity,and octylic hydroxamic acid was chosen to use in the following experiments.Reduced zeta potential showed the adsorption of the anionic collector on the mineral.By the adsorptive capability and IR(infrared ray)tests,the adsorption of octylic hydroxamic acid on diaspore was determined to be chemical absorption,which was greater than that of oleic acid,as it was absorption by hydrogen bond. 展开更多
关键词 octylic hydroxamic acid DIASPORE KAOLINITE BAUXITE FLOTATION
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Stereoselective synthesis and crystal structure of 4,6-O-benzylidene-N-octyl-D-allosamine hydrochloride
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作者 Fu Yi Zhang Chun Li Wu +1 位作者 Cui Zhang Hong Min Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期798-801,共4页
The building block of N-alkyl derivative of allosamidin(chitinase inhibitor),4,6-O-benzylidene-N-octyl-D-allosamine hydrochloride was stereoselectively synthesized in two steps under mild conditions.Nucleophilic add... The building block of N-alkyl derivative of allosamidin(chitinase inhibitor),4,6-O-benzylidene-N-octyl-D-allosamine hydrochloride was stereoselectively synthesized in two steps under mild conditions.Nucleophilic addition of octylamine to 2- oxoglucopyranoside gave a‘carbonyl group transfer' product in 62%yield.Subsequent stereoselective reduction of newly formed C=O with NaBH_4 produced title compound in 75%yield.X-ray diffraction analysis indicates the title compound adopts syn 1,2,3 stereochemistry and chair-chair conformation.The crystal structure is stabilized by hydrogen bonds. 展开更多
关键词 2-Oxoglucopyranoside 4 6-O-benzylidene-N-octyl-D-allosamine hydrochloride X-ray structure
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2-Octyl-Cyanoacrylate Skin Adhesive Used as a Splinting Material in Auricular Surgery
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作者 Naoto Yamamoto Satoshi Yanagibayashi +4 位作者 Ryuichi Yoshida Hiroyuki Ogi Megumi Takikawa Akio Nishijima Eri Maruyama 《Modern Plastic Surgery》 2016年第4期21-26,共7页
In cases of auricular surgery, postoperative dressings are thought to be important for keeping auricular contour and in helping to prevent from dressing failures due to edema or subcutaneous hematoma, which may result... In cases of auricular surgery, postoperative dressings are thought to be important for keeping auricular contour and in helping to prevent from dressing failures due to edema or subcutaneous hematoma, which may result in fibrous or cartilaginous proliferation. However, it is often difficult to achieve success with standard dressings because of the complicated shape of the auricle. We used 2-octyl-cyanoacrylate skin adhesive to dress the auricle after different types of auricular procedures (five cases of cryptotia, two of prominent ear, two of severe auricular laceration, two of skin grafting and one of flap repair of the partial auricle defect). The 2-octyl-cyanoacrlaate skin adhesive was applied to the suture line and the operated and peripheral areas for wider coverage. No dressing materials were placed over the surface. In all cases, the desired outcome was achieved, without subcutaneous hematoma, wound dehiscence, and wound infection. Contact dermatitis caused by the skin adhesive was not observed in any of the cases. Dressing and splinting after auricular surgery can be simply and successfully achieved using 2-octyl-cyanoacrylate skin adhesive. There is no need for more complicated dressings and post-surgical dressing changes, resulting in higher patient satisfaction. 展开更多
关键词 Auricular Surgery Postoperative Dressings Splinting Material 2-octyl-Cyanoacrylate Skin Adhesive
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Ca^(2+)影响辛基异羟肟酸浮选独居石的FTIR、XPS研究
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作者 刘荣祥 杨占峰 +3 位作者 李解 曹钊 李强 李计川 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第10期2959-2967,共9页
独居石浮选体系中往往有方解石、萤石、白云石等大量的伴生矿,而这些伴生矿在独居石矿中会解离出大量的Ca^(2+),而Ca^(2+)往往会影响矿浆浮选环境。为此,通过Ca^(2+)的溶液化学计算、独居石浮选试验,以及浮选条件下作用的独居石表面红... 独居石浮选体系中往往有方解石、萤石、白云石等大量的伴生矿,而这些伴生矿在独居石矿中会解离出大量的Ca^(2+),而Ca^(2+)往往会影响矿浆浮选环境。为此,通过Ca^(2+)的溶液化学计算、独居石浮选试验,以及浮选条件下作用的独居石表面红外光谱分析(FTIR)和X射线光电子能谱(XPS),分析研究Ca^(2+)的影响。Ca^(2+)的溶液化学计算显示,在水溶液中,随着pH值的升高,Ca^(2+)分别以离子态、羟基络合物和氢氧化合物的形式存在,当pH值在7~8之间,优势组分为Ca^(2+)和Ca(OH)^(+)。独居石浮选结果表明,不添加Ca^(2+)时,捕收剂OHA不能充分的浮选独居石,回收率为75.37%;而在pH为8±0.5,加入3×10^(-4)mol·L^(-1)的Ca^(2+)剂量,可显著的提高OHA对独居石的浮选性能,回收率达到96.48%。由溶液化学计算可知,Ca(OH)+是活化独居石的优势组分;Ca^(2+)剂量大于3×10^(-4)mol·L^(-1)时浮选回收率下降幅度较大,说明Ca^(2+)剂量的进一步增加,反而抑制独居石浮选,只有一定剂量的Ca^(2+)有效的促进独居石浮选,这可能归因于Ca^(2+)剂量消耗了OHA的浓度,进而影响独居石的浮选。红外光谱分析表明,在Ca^(2+)的作用下,光谱中出现两个关键性的新峰,其一为1454 cm^(-1)处的N—O—H弯曲振动峰,其二为880 cm^(-1)处的O—N拉伸振动峰,而在2974和2928 cm^(-1)的有机峰—CH_(3)和—CH_(2)—峰明显增强,这些基团的出现表明发生了化学吸附且吸附强度大于纯独居石吸附OHA的效果。XPS分析表明,仅使用OHA吸附独居石,独居石表面的N元素相对含量较低,为0.61%,而Ca^(2+)处理后的独居石,OHA吸附独居石时,独居石表面的N元素相对含量较高,达到2.36,由此可以得出,Ca^(2+)会促进OHA吸附到独居石表面。从分峰拟合中可以看出,添加Ca^(2+)在独居石的解理面上氧原子与Ca(OH)^(+)反应形成O—Ca—OH基团,可以作为吸附OHA的新吸附位点,同时独居石的铈原子与OHA上的两个氧原子形成五元螯合物也作吸附位点,得出独居石表面可以有两个吸附位点,独居石表面的Ca和Ce原子的活性位点都能吸附OHA,有利于OHA在独居石表面吸附,形成更均匀更致密的OHA疏水吸附层,这就是Ca^(2+)在OHA浮选独居石的性能得到改善的原因。这项研究有助于丰富矿浆中金属离子的活化理论,也证实了有效的矿物浮选分离不仅仅依赖于捕收剂-矿物相互作用的强度,而在很大程度上依赖于浮选溶液的化学性质。利用或者控制表面反应是开发一种更高效、更经济的浮选工艺的主要技术手段。 展开更多
关键词 独居石 浮选 辛基异羟肟酸 钙离子 红外光谱 分峰拟合
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凝胶渗透色谱法测定辛基酚醛增粘树脂相对分子质量及其分布 被引量:1
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作者 王慧敏 刘丽 +2 位作者 贾爱瑞 张丽杰 谭东妮 《轮胎工业》 CAS 2024年第3期184-187,共4页
采用凝胶渗透色谱(GPC)法测定辛基酚醛增粘树脂相对分子质量及其分布,并研究辛基酚醛增粘树脂相对分子质量对其软化点和增粘效果的影响。确定的测试条件为:流速1.0 mL·min^(-1),柱温40℃,试样溶液质量浓度(2±0.2) mg·mL^... 采用凝胶渗透色谱(GPC)法测定辛基酚醛增粘树脂相对分子质量及其分布,并研究辛基酚醛增粘树脂相对分子质量对其软化点和增粘效果的影响。确定的测试条件为:流速1.0 mL·min^(-1),柱温40℃,试样溶液质量浓度(2±0.2) mg·mL^(-1);辛基酚醛增粘树脂的软化点和增粘效果随着其相对分子质量的增大而提高。 展开更多
关键词 凝胶渗透色谱 辛基酚醛增粘树脂 相对分子质量 软化点 增粘效果
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人参皂苷辛酸酯通过内质网应激诱导肝癌细胞免疫原性细胞死亡的机制研究
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作者 戴珍珍 黄青昕 +4 位作者 胡淇睿 吴汉城 潘瑶 邓泽元 陈芳 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第4期767-771,779,共6页
目的:探讨人参皂苷辛酸酯(Rh2-O)能否诱导Huh-7肝癌细胞免疫原性细胞死亡及可能机制。方法:体外培养Huh-7细胞,设置空白对照组、Rh2-O药物组及阳性对照组(米托蒽醌处理),CCK-8、流式细胞术分别检测细胞活力和凋亡,ELISA及化学发光法分... 目的:探讨人参皂苷辛酸酯(Rh2-O)能否诱导Huh-7肝癌细胞免疫原性细胞死亡及可能机制。方法:体外培养Huh-7细胞,设置空白对照组、Rh2-O药物组及阳性对照组(米托蒽醌处理),CCK-8、流式细胞术分别检测细胞活力和凋亡,ELISA及化学发光法分别检测细胞上清高迁移率族蛋白1(HMGB1)和三磷酸腺苷(ATP)含量,免疫荧光法检测细胞钙网蛋白(CRT)的膜外翻,荧光探针DCFH-DA检测细胞内ROS水平,Western blot检测细胞内质网应激信号通路相关蛋白表达。结果:Rh2-O可显著降低细胞活力,促进细胞凋亡,诱导细胞HMGB1分泌、ATP释放及CRT膜外翻,使细胞内蓄积大量ROS,提高内质网应激信号通路相关蛋白PERK、eIF2α、p-eIF2α表达(均P<0.05)。内质网应激抑制剂4-苯基丁酸(4-PBA)预处理可显著减弱Rh2-O诱导的CRT膜外翻(P<0.05)。结论:Rh2-O可诱导肝癌细胞发生免疫原性细胞死亡,其机制可能与Rh2-O激活内质网应激促进细胞CRT膜外翻有关。 展开更多
关键词 人参皂苷 辛酸酯衍生物 肝癌 免疫原性细胞死亡 内质网应激
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氟碳铈矿还原焙烧相变及浮选行为研究
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作者 赵英杰 汤家焰 +4 位作者 何嘉宁 赵芳 王晓平 王介良 曹钊 《金属矿山》 CAS 北大核心 2024年第4期142-149,共8页
白云鄂博矿选铁过程中常使用还原焙烧方法,焙烧过程中稀土矿物会发生物相转变,并对其浮选行为产生影响。通过XRD分析测试、SEM-EDS测试、浮选试验、接触角测试、Zeta电位测试、X射线光电子能谱(XPS)分析等手段研究了氟碳铈矿经过400、45... 白云鄂博矿选铁过程中常使用还原焙烧方法,焙烧过程中稀土矿物会发生物相转变,并对其浮选行为产生影响。通过XRD分析测试、SEM-EDS测试、浮选试验、接触角测试、Zeta电位测试、X射线光电子能谱(XPS)分析等手段研究了氟碳铈矿经过400、450、500、550℃焙烧后的物相变化,以及在两种捕收剂辛基羟肟酸(OHA)和二乙基己基磷酸酯(2ZHP)作用下对氟碳铈矿和500℃焙烧氟碳铈矿浮选行为的影响。XRD和SEM-EDS测试结果表明,450℃焙烧氟碳铈矿为REFCO_(3),500℃焙烧氟碳铈矿部分分解为RE_(3)O_(4)F_(3),550℃焙烧氟碳铈矿时彻底转变为新物质RE_(3)O_(4)F_(3)。捕收剂OHA对500℃焙烧氟碳铈矿生成的新物质RE_(3)O_(4)F_(3)浮选效果较差,2ZHP对氟碳铈矿REFCO_(3)和500℃氟碳铈矿焙烧产物RE_(3)O_(4)F_(3)的捕收能力相当。接触角测试表明,2ZHP更能够强化氟碳铈矿和500℃焙烧氟碳铈矿的表面疏水性,Zeta电位测试表明,相比较OHA而言,2ZHP能更有效地在焙烧后的氟碳铈矿表面吸附。XPS测试表明,OHA和2ZHP通过在矿物表面吸附起到捕收作用,2ZHP在焙烧后的氟碳铈矿表面吸附量更大,2ZHP也更适合用于焙烧后的氟碳铈矿的浮选。 展开更多
关键词 焙烧氟碳铈矿 物相变化 浮选 辛基羟肟酸 二乙基己基磷酸酯
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烷基葡萄糖苷的制备及应用
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作者 尚建平 樊贝贝 +3 位作者 邓芳艳 付琳 范华军 陈咏梅 《化学研究与应用》 CAS 北大核心 2024年第6期1207-1213,共7页
传统表面活性剂以石油基为原料,原料不可再生、生物降解率低,且对皮肤刺激性强、危害人体健康。针对以上问题,本文以可再生的葡萄糖为亲水基团,脂肪醇为疏水基团,通过Helferich法合成出一种绿色温和的非离子表面活性剂(APG-08),通过核... 传统表面活性剂以石油基为原料,原料不可再生、生物降解率低,且对皮肤刺激性强、危害人体健康。针对以上问题,本文以可再生的葡萄糖为亲水基团,脂肪醇为疏水基团,通过Helferich法合成出一种绿色温和的非离子表面活性剂(APG-08),通过核磁共振氢谱(H^(1)NMR)和碳谱(C^(13)NMR)对其结构进行表征,并对综合性能进行评价。结果表明:APG-08具有优异的表面张力、泡沫性能和较好的乳化性能;当其质量分数为1%,表面张力值为30.61mN·m^(2),发泡量为10.0mL,且在10min之内能保持泡沫体积不变。将APG-08加入到润肤乳液的配方中,并进行了一系列性能测试,符合GB/T29665-2013的相关规格要求。说明研制的非离子表面活性剂APG-08能够很好地满足化妆品用表面活性剂的要求。 展开更多
关键词 辛基-β-D葡萄糖苷 非离子型表面活性剂 Helferich法 性能测定 润肤乳液
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