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      • HG/T 4158-2010酸性艷紅P-5B(C.I.酸性紅249)Acid brilliant red P-5B(C.I. Acid red 249)

        本標準規定了酸性艷紅P-5B(C.I.酸性紅249,弱酸性艷紅B)產品的要求、采樣、試驗方法、檢驗規則以及標志、標簽、包裝、運輸和貯存。<br>本標準適用于酸性艷紅P-5B的產品質量控制。...

        2022-06-15 09:11:48瀏覽:3 acidRill

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      • HG/T 3435-2010酸性翠藍2G(C.I.酸性藍7)Acid turquoise blue 2G(C.I.Acid blue 7)

        本標準規定了酸性翠藍2G(C.I. 酸性藍7,酸性湖藍A)產品的要求、采樣、試驗方法、檢驗規則以及標志、標簽、包裝、運輸和貯存。<br>本標準適用于酸性翠藍2G的產品質量控制。...

        2022-06-12 11:24:36瀏覽:2 blueacidquo

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      • HG/T 3751-2011酸性黑NT(C. I.酸性黑210)Acid black NT(C.I.Acid black 210)

        本標準規定了酸性黑NT(C.I.酸性黑210)產品的要求、采樣、試驗方法、檢驗規則以及標志、標簽、包裝、運輸和貯存。<br>本標準適用于酸性黑NT的產品質量控制。...

        2022-06-06 18:57:58瀏覽:5 acidlackblack

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      • Microporous Silica-supported Poi yoxometal ate Catalyst H3PW12O400/SiO2 with High Activity for Aceta

        Keggin-type polyoxometalates (POMs) whose representative is H3PW12O40(PW12) exhibits a unique combination of physical and chemical properties. They have been widely used as acid catalysts in homogeneous and heterogeneous reaction systems. However, the catalytic activity of PW12 is so limited due to its very low specific surface area (≤9 m2/g)[1] that polar molecules can only react on its surface....

        2020-12-22 21:24:13瀏覽:33 silica-supported12-tungstophosphoricacidcatalysisacetalreaction

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      • Acidic catalysis of microporous polyoxometalate H3PW12O40/SiO2 in acetal reaction between benzaldehy

        Microporous Keggin-type polyoxometalate material was synthesised by supporting H3PW12O40 into a silica matrix via a sol-gel technique. The silica-supported 12-tungstophosphoric acid (H3PW12O4o/SiO2) obtained is insoluble and readily separable porous materials with uniform micropores (0.57 nm) and a high specific surface area (350.5 m2/g) in oxygen-containing polar solvents. H3PW12 O40/SiO2 was characterized by infrared spectrophotometer (IR), ultraviolet-visible spectrophotometer (UV-vis), inductively coupled plasma (ICP), thermogravimetric analysis (TGA) and Brunner-Emmett-Teller method (BET) measurements. H3PW12O40/SiO2 obtained catalyzed the acetal reaction between benzaldehyde and ethylene glycol to produce 2-phenyl-1, 3-dioxolane more efficiently than the typical solid acids such as SO2-4/ZrO2, Nafion-H and H-ZSM-5. Conversion was 93.8 % for benzaldehyde during the reaction period of 2 h.H3PW12O40/SiO2 kept its initial activity during three times of reuse. The initial acetal reaction follows a second-order kinetics model at 298 K....

        2020-12-22 21:24:13瀏覽:47 silica-supported12-tungstophosphoricacidcatalyzeacetalreaction

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      • Characteristic of hyaluronic acid derivative films cross-linked by polyethylene glycol of low water

        Objective: To test the characteristics of byaluronic acid (HA) derivative cross-linked by polyethylene glycol films of low water content. Methods: The cross-linked HA film with 200 μm thickness was got at atmospheric pressure at 25℃ for 5 d. After dried, cross-linked films of 10 mm×10 mm were weighed and immersed in phosphate buffered saline (PBS pH 7.45) at 37℃ for 24 h. Then the solution fraction and water content were estimated. Meanwhile, cross-linked HA derivative films were immersed in phosphate buffered saline (PBS: pH 7.45) at 37℃ for determined time and then implanted subcutaneously in the back of white rats to test in vitro or in vivo degradation characteristic. Results and Conclusion: HA hydrogel cross-linked by polyethylene glycol with water content is as low as 60% and this kind of HA derivative has a slow degradation rate....

        2020-12-22 21:24:13瀏覽:53 hyaluronicacidpolyethyleneglycolwatercontentdegradationrate

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      • Synthesis and Characterization of a Novel Functional Biodegradable Copolymer-Poly(lactic acid-4-hydr

        A series of poly(lactic acid-4-hydroxyproline-polyethylene glycol) (PLA-Hpr-PEG) copolymers were synthesized by direct melt copolymerization of D,L-lactic acid and 4-hydroxyproline with different feed amount of polyethylene glycol (PEG) 0.1%, 0.5%, 1% and 5%, respectively. The properties of these copolymers were characterized by using IR spectroscopy, proton nuclear magnetic resonance (1H-NMR) spectroscopy, gel permeation chromatography (GPC), X-ray diffraction and differential scaning calorimetry (DSC). PLA-Hpr-PEG are amorphous copolymers. Copolymers showed increasing water uptake capacity with increasing PEG percentage in the feed, which result in an increasing degradable rate in phosphate buffer solution (pH 7.4) at 37℃....

        2020-12-22 21:24:13瀏覽:32 Lacticacid4-hydroxyprolinepolyethyleneglycol

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      • PREPARATION AND PROPERTIES OF POLY (LACTIC ACID-CO-GLYCOL TEREPHTHALIC ACID) COPOLYESTER

        To obtain a kind of biodegradable polymer material with satisfactory properties, a new biodegradable copolyester poly(lactic acid-co-glycol terephthalate) (PETA), was synthesized from three monomers of lactic acid, glycol and terephthalic acid. The resulting copolyesters, PETA, were characterized by FT-IR, 1H-NMR, DSC, TGA and by the ways of weight loss rate to characterize their biodegradability. The findings in this work indicated that, the TmS and TdS of copolyesters PETA increased with increasing contents of the terephthalic acid units. From the biodegradation tests in natural soil, boiling water, acid buffer solution and alkali buffer solution, it was shown that the biodegradability of copolyesters PETA decreased with increasing contents of the terephthalic acid units....

        2020-12-22 21:24:13瀏覽:33 LacticacidglycolTerephthalicCopolyesterthermalproperties

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      • Characteristics of Hyaluronic Acid Derivative Cross-linked by Polyethylene Glycol

        Characteristic and dynamic viscosities of Hyaluronic acid ( HA ) derivative modified by polyethylene glycol (PEG) were tested with different reaction times (6 h,12 h,18 h and 24 h ) , different molar ratio of HA/PEG ( 1/10,1/5,1/3 and 1/2), different molecular weight of PEG(400,6 000 and 20 000) and mass fraction is 0.4% by Wushi Viscosimeter and L- 90 Rheometer at 25 ℃. Characteristic viscosity of HA derivative had the largest value in 12 h, which decreased with increasing of PEG molecular weight, but its aqueous dynamic viscosity increased with increment of PEG molecular weight. Meanwhile, we tested dynamic mechanic properties of HA derivative by 3ARES3 Rheometer at 25 ℃ to study viscoelastic changes and to compare change difference from viscosity to elasticity with the changes of vibration frequency between unmodified HA and HA derivative.Change from low vibrated frequency to high one of solution resulted in change from viscosity to elasticity of solution. In conclusion, as to the rheological properties, structure-modified HA derivative meets the requirement of biomnterial ....

        2020-12-22 21:24:13瀏覽:71 hyaluronicacidcharacteristicviscositydynamicalviscoelastic

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      • Rheological and Biological Characteristics of Hyaluronic Acid Derivative Modified by Polyethylene Gl

        Hyaluronic acid (HA) was chemically modified by polyethylene glycol. Meanwhile,the dynamic mechanics properties of HA derivative and its viscoelastic changes were measured on 3ARES3 Rheometer (Japan) at 25 ℃. Dried cross-linked films of 10×10 mm2 were immersed in phosphate buffered saline(PBS: pH 7.4) at 37 ℃ with different time periods to measure its water content and in vitro degradation. Moreover, cell cultured solutions, which were in the different cultivation vesse with 1 mg/mL Solution of HA derivative as doing experimental sample for 2 d, 4 d and 7 d, were observed, respectively, by an inverted discrepancy microscope. The cell relative growth rate was analyzed with the SPSS10.0 mathematic statistic software. Based on the above experiments,structure-modified HA derivative can meet the requirements of biomaterials in view of rheological and degradation in vitro and cytotoxicity charactereistics from clinical medical aspect under this experiment conditions....

        2020-12-22 21:24:13瀏覽:68 hyaluronicacidviscoelasticitywatercontentdegradationcytotoxicity

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      • 壓鑄鎂合金植酸轉化處理中添加劑的研究

        通過在植酸基礎轉化液中添加兩種不同組成的成膜促進劑制備鎂合金植酸轉化膜,采用SEM、EDS及失重法研究了添加劑對轉化膜結構、形貌及耐蝕性能的影響.結果表明:經植酸轉化處理后,鎂合金表面耐蝕性能均得到了大幅提高,120 h鹽水浸泡后失重率僅為鎂合金基材的1/5;Ca(NO3)2、NH4VO3及Na2C4 H4O6·2H2O組合添加劑的加入有利于改善膜層結構和致密性,轉化膜由完整、致密且與基材結合緊密的內層和網紋的外層組成,耐蝕性能較純植酸轉化膜提高1倍,而NaF、Na2B4O7及Na2C4H4O6·2H2O的組合添加劑則對轉化膜結構和耐蝕性能影響不顯著....

        2020-12-06 21:11:24瀏覽:18 鎂合金添加劑植酸轉化膜失重率magnesiumalloyadditivephyticacidconversioncoating

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      • Selection of Anodic Material Used in Electrolytic Process for Producing Hypophosphorous Acid

        Black lead, Ti-Ru and Ti-PbO2 were used as anode and stainless steel was used as cathode.The electrolytic process of producing hypophosphorous acid with four-compartment electrodialytic cell was studied. The comparison of some factors, such as anodic voltage, product concentration and current efficiency, of black lead, Ti-Ru, and Ti-PbO2 electrodes was conducted. As a result, the Ti-PbO2 electrode is the optimal anode material used, it can be in electrolytic process for producing hypophosphorous acid....

        2020-11-22 17:58:37瀏覽:19 Hypophosphorousacidelectrolysisanodicmaterial

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      • Process for Separation of Petroleum Acids from Crude Oil

        A new technique for separation of petroleum acids from crude oil was proposed. The method relates to processes for treating acidic oils or fractions thereof to reduce or eliminate their acidity by addition of effective amounts of crosslinked polymeric amines such as polypropylene amine and anionic exchange resins having amino-groups. Petroleum acids contained in the mixture can be extracted by a complex solvent. The results indicate that more than 80 % of the petroleum acids are removed and the process does not cause environmental pollution because all the solvents are recovered and reused in the test....

        2020-11-10 09:33:08瀏覽:31 crudeoilPetroleumacidnaphthenicseparationpolypropyleneamine

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      • 流體高效輸送節能技術在硫酸、磷復肥裝置循環水系統中的應用分析

        針對目前我國大部分硫酸、磷肥生產裝置循環水系統中普遍存在水泵運行效率低、能耗高、振動噪聲大以及汽蝕等問題,提出實施流體高效輸送節能改造技術.大量的實驗及成功的改造案例說明,實施該項技術改造后可以在節能的同時提高運行效率,并且能夠取得良好的經濟效益和社會效益....

        2020-11-10 09:33:08瀏覽:28 硫酸磷肥循環水系統流體高效輸送技術節能改造sulfuricacidPhosphatefertilizercirculatingwater

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      • 無填料噴霧冷卻塔在磷酸循環水系統中的應用

        循環水冷卻效果的好壞是影響磷酸生產的關鍵因素。由于傳統填料冷卻塔存在諸多問題,故對其進行改造。改用無填料和高效低壓離心噴霧裝置的空塔,有效解決了填料塔分水不均、飄雨嚴重、冷卻效率下降等問題,循環水經冷卻塔進出口溫差提高1~2℃,且減輕了設備檢修清堵和維護的工作量和費用。...

        2020-11-10 09:33:08瀏覽:25 磷酸生產循環水冷卻水冷卻塔無填料phosphoricacidproductioncirculatingwatercooling

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      • 三氯異氰尿酸在大型循環水系統中的應用分析

        為改善神木化工公司循環水系統單純加氯氣殺菌導致的循環水質惡化狀況,采用三氯異氰尿酸代替氯氣進行殺菌。通過一期循環水系統加三氯異氰尿酸、二期循環水系統連續加氯氣殺菌數據分析,闡明了加三氯異氰尿酸后系統中Cl-不會升高的原因,并針對一二期循環水系統加三氯異氰尿酸后導致的NO2-升高問題,提出了解決辦法。證明了三氯異氰尿酸在大型循環水系統中應用的可行性,并提出改進措施。...

        2020-11-10 09:33:08瀏覽:23 三氯異氰尿酸氯離子亞硝酸根交替殺菌法Trichlorinatedisocyanuricacidchlorideionnitrite

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      • 丙烯酸價漲利增能走多遠--涂料業重要原料丙烯酸市場觀察與展望

        近年來,丙烯酸作為涂料業的重要原料在化工市場表現極為耀眼,一度洛陽紙貴、價漲利增,成為化工市場亮點。對其市場情況進行了觀察,分析了市場波動的原因,并展望了未來走向。...

        2020-10-26 22:14:25瀏覽:18 丙烯酸化工市場價格走向acrylicacidchemicalindustrymarketpricetrend

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      • 丙烯酰胺-丙烯酸-丙烯羥肟酸共聚物乳液脫除電鍍廢水中的重金屬離子

        采用反相乳液聚合法合成了丙烯酰胺(AM)-丙烯酸(AA)-丙烯羥肟酸(AHA)共聚物乳液.考察了該共聚物配方中丙烯羥肟酸用量,共聚物乳液的投量和pH值對電鍍廢水中重金屬離子的脫除效果.結果表明:pH=10,丙烯羥肟酸在共聚物乳液中的用量>15%,共聚物乳液的投量為20~30 mg/L時,脫除電鍍廢水中重金屬離子的效果最好,Cr、Cu、Ni和Zn等重金屬離子的脫去率>99.5%,處理后的水中每種重金屬離子濃度<0.2mg/L....

        2020-10-26 22:14:25瀏覽:15 反相乳液羥肟酸重金屬離子脫除廢水inverseemulsionhydroxamicacidmetalionsremoval

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      • 丙烯酸雙環戊烯基酯合成工藝的研究

        以丙烯酸和雙環戊二烯為原料合成了丙烯酸雙環戊烯基酯。實驗結果表明:以三氟甲磺酸為催化劑,反應溫度為90℃,丙烯酸與DCPD摩爾比為1.1∶1,催化劑用量為反應液總質量的0.1%,反應時間為4h、攪拌速率為200r/min的條件下,DCPD轉化率在98%以上,DCPA選擇性在95%以上。...

        2020-10-26 22:14:25瀏覽:27 丙烯酸雙環戊二烯丙烯酸雙環戊烯基酯催化劑合成acrylicaciddicyclopentadienedicyclopentadienyl

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      • 丙烯酸與異丁烯酯化合成丙烯酸叔丁酯動力學

        為實現丙烯酸與異丁烯酯化合成丙烯酸叔丁酯的工業化,在間歇釜式反應器內,研究了磺酸改性SBA-15介孔分子篩催化丙烯酸與異丁烯加成酯化合成丙烯酸叔丁酯的本征反應動力學。結果表明,在攪拌轉速大于400 r/min,催化劑粒徑為0.15~0.18 mm,可消除內、外擴散影響。測定了酸烯酯化合成丙烯酸叔丁酯的本征反應動力學數據,建立了冪級數反應動力學方程,采用非線性最小二乘法擬合得到模型參數,得到酯化反應的正逆反應活化能分別為33.8和61.7 kJ/mol,異丁烯二聚反應的正逆反應活化能分別為42.7和91.6 k J/mol,實驗測定值與模型計算值吻合較好。...

        2020-10-26 22:14:25瀏覽:18 丙烯酸異丁烯丙烯酸叔丁酯SO3H-SBA-15分子篩催化劑加成酯化acrylicacidisobutyleneTert-butyl

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      • 丙烯酸環己酯的合成研究

        以丙烯酸和環己醇為原料合成丙烯酸環己酯,考察了不同催化劑、阻聚劑用量、催化劑用量、醇酸比及反應時間對丙烯酸轉化率和選擇性的影響,得到的最佳工藝條件為:催化劑為甲基苯磺酸,用量為1%,醇酸比為1.5,阻聚劑為3‰,帶水劑用量為5%,丙烯酸轉化率大于90%,選擇性大于80%....

        2020-10-26 22:14:25瀏覽:27 丙烯酸環己醇丙烯酸環己酯甲基苯磺酸acrylicacidcyclohexanolcyclohexylacrylate

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      • 氯化聚丙烯的磺化改性研究與應用

        以氨基磺酸為磺化劑對氯化聚丙烯(CPP)進行磺化改性,研究了氨基磺酸的用量、反應溫度和時間對磺化度的影響,獲得了較佳的反應條件:m(NH2SO3H)/m (CPP)=0.08,溫度60℃,時間80h.在此條件下可制得磺化度為1.56 mol/kg的磺化CPP.通過紅外光譜對磺化CPP進行了表征.將磺化改性的CPP與丙烯酸酯聚合,制備了水性磺化CPP-丙烯酸酯乳液.以此乳液制備金屬防腐涂料,所得涂膜附著力0~1級,硬度3B~ 2B,柔韌性>2 mm,在3% NaCl溶液中浸泡45 d和鹽霧腐蝕試驗300 h后完好.該磺化改性CPP可用于制備水性金屬防腐涂料....

        2020-10-26 22:14:25瀏覽:26 氯化聚丙烯氨基磺酸磺化改性丙烯酸酯乳液聚合防腐涂料chlorinatedpolypropyleneSulfamicacid

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      • 丙烯腈與丙烯酸共聚合

        以偶氮二異丁腈為引發劑,研究了丙烯腈與丙烯酸在環己烷中的自由基溶液共聚合反應。探討了單體質量分數,引發劑質量分數,反應溫度等對共聚反應的影響。用烏式粘度計測定了產物的相對分子質量。用IR和TG對產物的結構和性能進行了表征。研究結果表明,最佳反應條件是:總單體質量分數30%,AIBN占總單體質量分數5%,反應溫度為70℃,反應時間為4 h。...

        2020-10-26 22:14:25瀏覽:23 丙烯腈丙烯酸溶液共聚合acrylonitrileacrylicacidcopolymerization

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      • 烏索酸的生產工藝

        Production of ursolic acid, the anti-hepatitis effective composition from natural plant,Sambucus chinensis Lindl.was carried out and the scale-up preparation technology was studied.Extraction of the herb Sambucus chinensis Lindl.was extracted in reflux with 7 volume times of refluxing ethanol at 80℃ for 1 h for two times.The extract was purified with a selt-made specific impurity remover "YCXY-1" to yield ursolic acid of high purity.A new "Extraction/Gelation" technology for the production of ursolic acid was developed. The specific impurity remover "YCXY-1" showed high effectiveness in purification. The purity of the mass-produced ursolic acid was up to 99.8%. The chemical structure of the product was confirmed by the physicochemical constants and spectroscopic identification. The production of high-purity ursolic acid was optimized with natural plant as raw material and with only ethanol as extracting solvent. The difficulties such as isolation and impurity removal were addressed effectively. The novel technology is reasonable, convenient, practical, low-cost, high-yield, suitable for mass production....

        2020-10-26 22:14:25瀏覽:19 SambucuschinensisLindl.ursolicacidextractionandseparationproduction

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      • Lead exposure increases oxidative stress in the gastric mucosa of HCI/ethanol-exposed rats

        AIM: To investigate the role of reactive oxygen species in the ulcer-aggravating effect of lead in albino rats.METHODS: Albino Wistar rats were randomly divided into three groups and treated orally with 100 mg/L (low dose) or 5000 mg/L (high dose) of lead acetate for 15 wk. A third group received saline and served as control.At the end of wk 15, colorimetric assays were applied to determine the concentrations of total protein and nitrite, the activities of the oxidative enzymes catalase and superoxide dismutase, and lipid peroxidation in homogenized gastric mucosal samples.RESULTS: Exposure of rats to lead significantly increased the gastric mucosal damage caused by acidified ethanol. Although the basal gastric acid secretory rate was not significantly altered, the maximal response of the stomach to histamine was significantly higher in the lead-exposed animals than in the unexposed control group. Exposure to low and high levels of lead significantly increased gastric lipid peroxidation to 183.2% ± 12.7% and 226.1% ± 6.8% of control values respectively (P < 0.0). On the other hand, lead exposure significantly decreased catalase and superoxide dismutase (SOD) activities and the amount of nitrite in gastric mucosal samples.CONCLUSION: Lead increases the formation of gastric ulcers by interfering with the oxidative metabolism in the stomach....

        2020-10-22 17:35:41瀏覽:19 LeadUlcerlipidperoxidationCatalaseGastricacid

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      [!--page.stats--] 被公玩弄的年轻人妻

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