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      • YY 0119-2002骨接合植入物.金屬矯形用釘Implants for osteosynthesis--Metal correctional nail

        本標準規定了骨接合植入物--金屬矯形用釘的分類、要求、試驗方法、檢驗規則、使用說明書、標準、包裝、運輸和貯存等要求。本標準適用于金屬矯形用釘,該產品供骨科手術時作骨折內固定用。...

        2022-06-15 09:11:48瀏覽:2 correctionsynthesisimplant

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      • YY 0341.1-2020無源外科植入物 骨接合與脊柱植入物 第1部分:骨接合植入物特殊要求Non-active surgical implants. Osteosynthesis and spinal implants. Part1:Particular requirements for osteosynthesis implants

        YY 0341.1-2020無源外科植入物 骨接合與脊柱植入物 第1部分:骨接合植入物特殊要求Non-active surgical implants. Osteosynthesis and spinal implants. Part1:Particular requirements for osteosynthesis implants...

        2022-03-23 12:23:25瀏覽:25 requirementsrequirementsynthesis

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      • Synthesis of a novel UV-curable prepolymer neopentyl glycol diglycidyl ether diacrylate and its cure

        A novel UV-curable prepolymer neopentyl glycol diglycidyl ether diacrylate(NPGGEA)was synthesized by using neopentyl glycol diglycidyl ether(NPGGE)and acrylic acid(AA)as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were taken as follows: The concentration of N,N-dimethylbenzylamine, 0.80% of reactants; the concentration of p-hydroxyanisole, 0.3% of reactants; the reaction temperature, 90-110℃; the molar ratio of NPGGE to AA, 1:2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized NPGGEA to prepare a kind of UV-cured coating. Mechanical properties of the UV-cured films were determined, giving 28.75 MPa of tensile strength, 923.82 MPa of Young's modulus and 5.51% of elongation at tear....

        2020-12-22 21:24:13瀏覽:68 synthesisneopentylglycoldiglycidyletherdiacrylate(NPGGEA)acrylicacid(AA)

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      • Synthesis of polyethylenimine grafted with copolymers of polyethylene glycol and polycaprolactone an

        Copolymers mPEG-PCL were prepared and grafted onto polyethylenimine (PEI) to synthesize copolymers mPEG-PCL-g-PEI with low cytotoxicity. The mPEG-PCL-g-PEI could condense siRNA to form nanoparticles with positive zeta potential. These nanoparticles could delivery siRNA into cells to effectively inhibit the expression of target gene, which suggested that mPEG-PCL-g-PEl could serve as a highly efficient vector for siRNA delivery....

        2020-12-22 21:24:13瀏覽:43 copolymersNanoparticlesvectorsynthesis

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      • Stereoselective Synthesis of Polysubstituted Cyclopropanes from Poly(ethylene glycol)Supported Pyrid

        Polysubstituted cyclopropanes were efficiently prepared with poly(ethylene glycol)(PEG)as soluble support.The reaction of PEG-supported pyridinium ylide with arylidenemalononitrile(R=CN)or ethyl arylidenecyanoacetate(R=COOEt)in the presence of triethylamine(TEA)afforded PEG-supported cyclopropanecarboxylates,which were cleaved by 1% KCN/EtOH to obtain polysubstituted cyclopropanes with exclusive trans-selectivity and good yields....

        2020-12-22 21:24:13瀏覽:53 poly(ethyleneglycol)Pyridiniumylidesynthesiscyclopropane

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      • Thermodynamics and kinetics analysis of in-situ synthesizing AlN

        AlN powders were prepared by in-situ synthesis technique. It is a reaction of binary molten Al-Mg alloys with highly pure nitrogen. It was confirmed through thermodynamics calculation that Mg element in Al-Mg alloys can decrease oxygen content in the reacting system. Thus, nitridation reaction can be performed to form AlN. Moreover, an analysis of kinetics shows that the nitridation reaction of Al-Mg alloys can be accelerated and transferred rapidly with the increment of Mg content....

        2020-12-06 21:11:24瀏覽:24 Al-MgalloyIn-situsynthesisAlNMgthermo-dynamicaldynamics

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      • Synthesis of kalsilite from microcline powder by an alkali-hydrothermal process

        The properties of aluminosilicate kalsilite have attracted the interest of researchers in chemical synthesis, ceramic industry, biofu-els, etc. In this study, kalsilite was hydrothermally synthesized from microcline powder in a KOH solution. The microcline powder, rich in potassium, aluminum, and silicon, was collected from Mountain Changling in Northwestern China. The effects of temperature, time, and KOH concentration on the decomposition of microcline were investigated. The kalsilite and intermediate products were characterized by means of wet chemistry analysis, X-ray Diffraction (XRD), infrared spectrometry (IR), 29Si magic angle spinning nuclear magnetic reso-nance (29Si MAS NMR), 27Al MAS NMR, and scanning electron microscope (SEM). With increasing temperature, the microcline powder transforms into a metastable KAlSiO4 polymorph before transforming further into pure kalsilite. A mixture of both kalsilite and metastable KAlSiO4 polymorph is obtained when the hydrothermal reaction is carried out within 2 h;but after 2 h, kalsilite is the predominant product. The concentration of KOH, which needs to be larger than 4.3 M, is an important parameter influencing the synthesis of kalsilite....

        2020-11-22 17:58:37瀏覽:24 kalsilitemicroclinepotassiumhydroxidehydrothermalsynthesis

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      • Synthesis of the Complex Fluoride LiBaF3 through a Solvothermal Process

        The complex fluoride LiBaF3 is solvothermally synthesized at 180℃ and characterized by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. In the solvothermal process, the solvents, mole ratios of initial mixtures and reaction temperature play important roles in the growth of the single crystal....

        2020-11-11 22:33:38瀏覽:27 solvothermalsynthesiscomplexfluoride

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      • Synthesis of Nickel Sulfide Particles by Solvothermal Process

        Pyrite nickel disulfide and millerite nickel monosulfide have been successfully prepared by solvothermal method based on the reaction of Ni(NO3)2.6H2O and H2NC(S)NH2 in benzene and ethylenediamine (EDA). The final products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM). The effects of the solvent, reaction temperature and time on the morphology and phase of the products have been discussed....

        2020-11-11 22:33:38瀏覽:25 ChalcogenidessolvothermalsynthesisX-raydiffractionAnalysis

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      • Green Process for Synthesis of Zeolite with MFI Structure

        A clean and environmentally friendly new process for synthesis of zeolite with MFI structure was presented. This process through recycling of vented gas and mother liquor can reduce or avoid discharge of nitrogen-containing offgas and waste liquid without affecting the physical and chemical properties of synthetic zeolite, leading to green synthesis of zeolite. This process can help to cut corners on production cost to achieve the sustainable development....

        2020-11-10 09:33:08瀏覽:24 MFIzeolitegreensynthesis

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      • Mathematical modeling of a slurry reactor for DME direct synthesis from syngas

        In this paper,an axial dispersion mathematical model is developed to simulate a three-phase slurry bubble column reactor for direct synthesis of dimethyl ether (DME) from syngas.This large-scale reactor is modeled using mass and energy balances,catalyst sedimentation and single-bubble as well as two-bubbles class flow hydrodynamics.A comparison between the two hydrodynamic models through pilot plant experimental data from the literature shows that heterogeneous two-bubbles flow model is in better agreement with the experimental data than homogeneous single-bubble gas flow model.Also,by investigating the heterogeneous gas flow and axial dispersion model for small bubbles as well as the large bubbles and slurry (i.e.including paraffins and the catalyst) phase,the temperature profile along the reactor is obtained.A comparison between isothermal and non-isothermal reactors reveals no obvious performance difference between them.The optimum values of reactor diameter and height were obtained at 7 m and 50 m,respectively.The effects of operating variables on the axial catalyst distribution,DME productivity and CO conversion are also investigated in this research....

        2020-11-03 10:30:25瀏覽:23 modelinglarge-scaleslurrybubblecolumnoptimizationdimethylethersynthesis

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      • Overview of Fischer-Tropsch Synthesis in Slurry Reactors

        A brief review of Fischer-Tropsch synthesis specially in slurry reactors ispresented,
        covering reaction kinetics, activity and selectivity of catalysts, productdistribution, effects of process
        parameters, mass transfer and solubility of gas. Someimportant aspects of further research are
        proposed for improving both theories andproduction....

        2020-11-03 10:30:25瀏覽:28 Fischer-Tropschsynthesisslurryreactorkineticscatalystmasstransfer

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      • N-丙烯酰嗎啉的合成研究

        丙烯酸甲酯與嗎啉反應合成丙烯酰嗎啉,在反應溫度為85℃,嗎啉與丙烯酸甲酯的摩爾比為3.5∶1,甲醇鈉的加入量為丙烯酸甲酯物質量的0.3%,反應時間為3.5h的條件下,丙烯酸甲酯的轉化率可達99.9%以上,N-丙烯酰嗎啉的純度99.8%以上....

        2020-10-26 22:14:25瀏覽:15 丙烯酸甲酯丙烯酰嗎啉合成methylacrylateN-acryloymorpholinesynthesis

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      • 二氯丙烯胺的合成

        報道了以二氯乙酰氯與二烯丙摹胺為原料,通過一步反應合成二氯丙烯胺,分別用碳酸氧鈉和三乙胺作為縛酸劑.實驗結果表明,采用碳酸氫鈉作縛酸劑得到的產品純度更高,約為99.0%以上,顏色更加澄清透亮.并通過正交實驗得出該反應的較優工藝條件,目標化合物通過紅外、核磁等分析手段進行了確認....

        2020-10-26 22:14:25瀏覽:43 二氯丙烯胺一步反應縛酸劑正交實驗dichlorimidone-stepsynthesiscatalystoahogonaltest

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      • 韋瑞德合成工藝的優化

        對韋瑞德合成工藝進行優化.以腺嘌呤為起始原料,將其與 R-碳酸丙烯酯縮合反應制得(R)-9-(2-羥基丙基)腺嘌呤,經醚化、超聲輔助三甲基氯硅烷脫磷酸酯得到替諾福韋,再經碘甲基碳酸異丙酯酯化、成鹽得到最終產物韋瑞德,總收率為31%(以腺嘌呤計算),HPLC 純度達99.5%.該優化合成工藝成本低廉,收率高,步驟短,適合于工業化生產....

        2020-10-26 22:14:25瀏覽:27 (R)-9-(2-羥基丙基)腺嘌呤替諾福韋合成韋瑞德tenofovirsynthesis

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      • 西尼地平的合成工藝研究

        以乙酰乙酸甲氧基乙基酯、乙酰乙酸肉桂醇酯為起始原料,經中間體3-氨基巴豆酸肉桂醇酯,通過Aldol縮合、Hantzsch環合反應,合成出了鈣離子拮抗劑西尼地平。該合成工藝安全可行,操作簡單,適合工業化生產。...

        2020-10-26 22:14:25瀏覽:19 西尼地平鈣拮抗劑合成cilnidipinedihydropyridinecalciumantagonistsynthesis

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      • 阿那曲唑的合成工藝改進

        通過相轉移催化反應合成阿那曲唑采用a,a,a',a',5-五甲基-1,3-苯二乙腈為起始原料,在溴化劑N-溴代丁二酰亞胺作用下溴化生成中間體3,5-二[(2,2-二甲基)氰基甲基]-溴甲基苯,所得溴代中間體進而與1,2,4-三氮唑在水及有機溶劑中采用相轉移催化縮合生產阿那曲唑??偸章蔬_75%。...

        2020-10-22 17:35:41瀏覽:28 阿那曲唑相轉移催化合成Anastrozolephasetransfercatalystsynthesis

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      • 氟哌酸合成工藝優化

        目的:本文主要從氟哌酸的合成路線出發,探討氟哌酸合成工藝的優化方法。方法通過對氟哌酸的合成路線進行分析,探討可以跟上時代腳步的新合成工藝。結果氟哌酸合成工藝的優化主要包括三種:縮哌嗪和乙基化合成新工藝、7-位氟取代合成新工藝以及硼螯合物合成新工藝。結論隨著科學技術的不斷進步和社會的迅速發展,醫藥技術的發展進程也在不斷加快,氟哌酸作為第三代喹諾酮類抗菌藥物,具有副作用小、和其他抗菌素無交叉耐藥性、組織滲透性好、生物利用度高、抗菌譜廣以及抗菌作用強等特點,特別是對于革蘭陰性桿菌具有非常強的殺菌作用。再加上吸收快、服用方便,目前已經廣泛應用與尿道炎、腎盂腎炎、扁桃體炎以及咽喉炎等的治療中。...

        2020-10-22 17:35:41瀏覽:23 氟哌酸合成工藝合成路線反應機理優化Norfloxacinsynthesisprocesssyntheticroutethe

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      • Ripasudil的新合成工藝

        4-氟異喹啉-5-磺酰氯與(S)-2-氨基-N-(叔丁氧羰基)-N-(3-叔丁基二甲基硅烷氧基丙基)丙胺發生偶聯反應,經TBAF脫去羥基保護后通過Mitsunobu反應自身環合,最后脫氨基保護得到青光眼治療藥物ripasudil,總收率31.3%....

        2020-10-22 17:35:41瀏覽:29 ripasudil青光眼合成glaucomasynthesis

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      • Synthesis of carbon nanofibers by ethanol catalytic combustion technique

        A general, simple and economic synthetic method for synthesizing carbon nanofibers was presented. In the method, ethanol was employed as carbon source; metal salts such as nickel nitrate, ferric nitrate and ferric chloride were used as catalyst precursor respectively; copper plate was employed as the support material. A lot of products were obtained by catalytic combustion deposition of ethanol vapor. Then the as-prepared carbon nanofibers were characterized by field-emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, energy dispersion X-ray spectroscopy and selected-area electron diffractometry. By analyzing the results of characterization, the conclusions are as follows: 1) the large catalyst particles tend to formlarge-diameter CNFs, small catalyst particles are inclinable to form small-diameter CNFs; 2) the morphology of the catalyst can affect the final morphology of the CNFs. Moreover, the possible growth mechanisms were proposed and the degree of graphitization of samples was estimated by Raman spectroscopy characterization....

        2020-10-22 17:35:41瀏覽:26 synthesisethanolcatalyticcombustioncarbonnanofibersgrowthmechanismdegree

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      • Fe/SiO2納米復合物上合成氣制低碳烯烴催化性能研究

        分別采用一步合成法和常規共沉淀法制備了 Fe/ SiO 2催化劑,通過 N2物理吸附、X 射線衍射、透射電鏡、傅里葉變換紅外光譜和程序升溫還原等方法對催化劑進行了表征,并在固定床反應器中對其費托合成制低碳烯烴的催化性能進行了評價。結果表明,與共沉淀鐵基催化劑不同,采用一步合成法制備的納米復合物主要由 Fe3 O4相構成,形貌呈規則球形,平均粒徑為30 nm,尺寸分布窄,更容易還原。一步合成法制得的 Fe/ SiO2催化劑對費托合成反應具有較高的活性和低碳烯烴選擇性、較低的甲烷選擇性和良好的穩定性。...

        2020-10-22 17:35:41瀏覽:36 合成氣費托合成低碳烯烴四氧化三鐵納米復合物syngasFischer-TropschsynthesislightOlefins

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      • 合成氣制低碳混合醇固定床催化劑的漿態床應用性能研究

        試驗將合成氣制低碳混合醇的固定床Cu-Fe-Mn-Co催化劑用于漿態床反應器,研究了反應溫度(200~270℃)、壓力(5.0MPa~7.0MPa)、原料氣空速(2713~5515h-1)、氫碳比(n(H2)/n(CO)=1.5/3.5)和攪拌器轉速(400~1200r/min)等工藝條件對催化劑性能的影響.結果表明:溫度對CO轉化率及時空產率影響顯著,260℃為低碳醇合成的最佳反應溫度;反應壓力在7.0MPa時總醇選擇性及時空產率達到最高值;空速的增加可以提高催化劑的低碳醇產能,減少CO2的生成,但同時原料氣轉化率隨之降低;氫碳比過低會造成總醇選擇性的大幅降低,過高又會導致甲醇選擇性的增加,選擇在2~2.5之間對低碳醇的生成較為有利;提高攪拌器轉速可以更大程度的消除或減小外擴散影響,但同時需兼顧攪拌槳對漿態床催化劑磨損的影響....

        2020-10-02 20:35:09瀏覽:29 低碳混合醇合成漿態床催化劑性能工藝條件lowcarbonmixedalcoholssynthesisslurrybedcatalyst

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      • 聯合兩段氧化制合成氣/F-T合成的GTL工藝和催化劑

        A novel process for catalytic oxidation of methane to synthesis gas (syngas), which consists of twoconsecutive fixed-bed reactors with air introduced into the reactors, integrated Fischer-Tropsch synthesis, was inves-tigated. At the same time, a catalytic combustion technology has been investigated for utilizing the F-T offgas togenerate heat or power energy. The results show that the two-stage fixed reactor process keep away from explosionof CH4/O2. The integrated process is fitted to produce diesel oil and lubricating oil in remote gas field....

        2020-10-02 20:35:09瀏覽:33 two-stagefixedreactorsyngasFischer-Tropschsynthesisgastoliquidprocess

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      • 三相床中合成氣制二甲醚宏觀動力學研究

        在三相高壓攪拌釜中,使用XR型復合催化劑,在溫度為220℃~260℃,空速為0.75 Lg~(-1).h~(-1)~1.35 Lg~(-1).h~(-1),壓力為3MPa~7MPa,反應進口yH_2/y_(co)為4.01~4.59的范圍內,攪拌轉速為900r.min~(-1)的條件下,研究了合成氣一步法制二甲醚宏觀動力學,考察了溫度、空速、壓力條件的變化對反應性能的影響.選取Iangmuir雙曲型動力學模型,采用遺傳算法和單純形法對宏觀動力學模型進行了參數估值,獲得動力學模型的參數,統計檢驗和殘差分析證實模型是適宜的....

        2020-10-02 20:35:09瀏覽:20 合成氣二甲醚直接合成XR催化劑三相床宏觀動力學syngasdimethyletherdirectsynthesisXRcatalyst

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      • 合成氣發酵梭菌C.autoethanogenum的生長特性與CO發酵性能

        為探討合成氣發酵乙醇的新工藝,對梭菌C.autoethanogenum的生長特性及CO發酵性能進行了研究.考察了不同碳源對C.autoethanogenum生長的影響,發現木糖是其生長的最佳底物.對生長培養基進行了改良,使C.autoethanogenum的菌體質量濃度提高2倍以上,代謝產物以乙酸為主,只產生少量乙醇.利用1L氣體采樣袋研究了C.autoethanogenum的CO發酵性能,在1.0g/L酵母膏的發酵培養基中經過兩次CO發酵后,乙醇質量濃度達3.464 g/L,CO乙醇轉化率達51.7%.研究表明:N2環境、180℃、4MPa下,20 min高溫液態水處理蔗渣得到的水解液可用于C.autoethanogenum的培養,培養液再進行CO發酵,經過一次發酵后得到的乙醇質量濃度為3.13g/L,CO乙醇轉化率為46.9%,與之前兩次發酵的結果接近,但是發酵時間大大縮短....

        2020-10-02 20:35:09瀏覽:53 合成氣乙醇一氧化碳氣體發酵synthesisgasethanolcarbonmonoxidefermentation

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      [!--page.stats--] 被公玩弄的年轻人妻

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        2. <blockquote id="mxhh4"></blockquote>