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1.
本文研究了甘蔗渣中性亚硫酸钠制浆的最佳工艺条件。研究结果表明,甘蔗渣中性亚硫酸钠制浆采用下列工艺条件:Na2SO3用量w为18%,Na2CO3用量w为3%,液比为1:5,最高温度165℃,升温2h,保温1h,在此条件下,纸浆得率w为65.83%,硬度(高锰酸钾值)9.14,白度95%(ISO),不透明度92.65%,并可得到较好的纸浆强度。  相似文献   

2.
甘蔗经榨糖后的蔗渣往往成为废弃物,其实蔗渣中还含有葡萄糖、果糖、单糖、淀粉、蛋白质等营养物质。蔗糖中所含的纤维素经过酸水解或微生物水解,还可以变成单糖。而牛粪中也含有粗蛋白和纤维素等营养成分。据报道,台湾省利用牛粪与甘蔗渣混合发酵后,作为饲料养牛已获成功。最近我们也进行了喂猪试验,结果效果很好。我们分两组试验,比例分别是40%鲜牛粪,50%切碎的甘蔗渣,10%的混合糠;50%的鲜牛粪,40%切碎的甘蔗渣,10%的混合糠。把原料按比例混合均匀后,按照厌  相似文献   

3.
我国泥炭资源非常丰富,贮量约为50亿吨。泥炭不仅可用作能源,还可将其中所含丰富的纤维素和半纤维素水解为单糖,制得含有蛋白质的饲料酵母;不能被酸水解的残渣可进一步加工成合成饲料酵母,从而节约大量粮食。 泥炭的水解是用稀酸溶液使泥炭中所含的纤维紊和半纤维素转化成单糖,单糖产率愈高,利用价值愈大。笔者在大量实验的基础上,研究  相似文献   

4.
对江西三处嫩毛竹自然制浆过程中的化学成分变化进行了测定,得知在此过程中,嫩竹木素下降50% ̄70%,半纤维素下降20% ̄30%;纤维素含量相对提高25% ̄45%,不同的土法制浆工艺得到不同质量的纸张,其化学成分也有明显差异。同时在实验室模拟了嫩竹发酵过程,对其化学成分变化进行了监测。结果表明,经2.5%为液浸泡嫩竹70d(室温),木素含量下降45%左右,半纤维素变化很小;用天然水浸泡嫩竹70d(室  相似文献   

5.
木质纤维原料各组分温和液化行为   总被引:1,自引:0,他引:1  
为开发可再生资源和缓解能源危机,研究了木质纤维原料的常压温和液化过程。在浓硫酸催化下,将甘蔗渣、甘蔗渣综纤维和甘蔗渣纤维素在乙二醇中130~190℃液化。对不同液化条件下残渣率、产物质量分布和红外谱图的分析。结果表明:在较低温度下,纤维素不易液化,半纤维素和木质素易液化;在较高温度下,纤维素可有效液化,木质素和半纤维素易发生再聚合形成不溶残渣;先较低温度再较高温度两步液化可有效降低残渣率。纤维素和半纤维素液化产物主要分布在水相;木质素产物主要分布在丙酮相;残渣同时来自三种组分。  相似文献   

6.
对江西三处嫩毛竹自然制浆过程中的化学成分变化进行了测定,得知在此过程中,嫩竹木素下降50%~70%;半纤维素下降20%~30%;纤维素含量相对提高25%~45%。不同的土法制浆工艺得到不同质量的纸张,其化学成分也有明显差异。同时在实验室模拟了嫩竹发酵过程,对其化学成分变化进行了监测。结果表明,经2.5%石灰液浸泡嫩竹70d(室温),木素含量下降45%左右,半纤维素变化很小;用天然水浸泡嫩竹70d(室温),半纤维素略有下降,木素则几乎没变,先用石灰水预浸3周,再改用自选的芽抱菌液浸泡嫩竹,经1周就达制浆水平,木素下降59%。还对分析方法做了些探索。  相似文献   

7.
安络小皮伞[Marasmius androsaceus(L:Fr)Fr]中水溶性多糖…   总被引:1,自引:0,他引:1  
用小提取的安络小皮伞的多糖,经醇析,真空干燥后,用sepharose 4B柱层析,酚一H2SO4法检测其多糖分布,紫外吸收法(280nm)检测其蛋白质分布,表明提取物为多糖和糖蛋白的混合物,总糖含量为30.5%。lorry法和克氏定氮法测定蛋白质含量15%。采用P.C和G.C法测定,结果提取物中的多糖由三种中性单糖组成,其摩尔比为:GLC:Man:FUC=1.2:3:1.7。用Fehling试剂法  相似文献   

8.
用两步水解法糖化甘蔗渣。发现用1.0%FeCl_3和1.0%HCl混合液作为催化剂,即使在较低温度下就能得到相当高的还原糖产率。研究了两步法无机盐催化反应的动力学。可以用一个动力学方程式描述常压和高压下的甘蔗渣糖化反应,和实验数据拟合良好。计算了水解反应和单糖分解反应的活化能。  相似文献   

9.
超临界CO2萃取薯蓣皂苷元的研究   总被引:8,自引:1,他引:8  
实验研究超临界C02萃取穿山龙水解物中薯蓣皂苷元的工艺条件.采用单因素法确定了超临界CO2萃取工艺的最佳条件,并对该法作了技术和经济上的评估.确定主要参数为:萃取压力35.0MPa,萃取温度45℃,以95%乙醇为携带剂,携带剂含量为3%.与有机溶剂提取方法相比,超临界CO2萃取法的收率及纯度均较高,且安全高效.超萃法直接从固体水解物滤渣中提取苷元,在设备规模较小时,生产能力较小.  相似文献   

10.
用改良的盐析法柑桔皮中提取果胶多糖,经DEAE-纤维素柱层析后分离出4种不同组分的果胶多糖。多糖经酸醇解后,分别用气相色谱和薄层层析分析其单糖组成成分。实验表明,4种不同组分果胶多糖其单糖的含量都不相同,其中半乳糖醛酸变化范围为81.85%-67.45%〈变动值较小。  相似文献   

11.
0Introduction Vanadiumplaysanimportantroleinmodernindustry,es peciallyinsteelandchemicalindustry.Forinstance,itscompoundsarewidelyappliedintheproceduresofvitrioland petroleumchemicalmanufactureascatalyzers[14].Vanadium hasseveralvalences,butgenerallyitslowvalencesturnintohighoneseasilyinenvironment[5].BecauseV(Ⅴ)isthemost stableandpoisonousone,weoftenlayemphasisonitinenvi ronmentalpollutioncontrol.Vanadiumexistsinenvironmentalwaterwithextremelylowconcentration.Inseawateritscontentislessthan…  相似文献   

12.
Zn(BTZ)2 was synthesized from the complex reaction between zinc acetate dihydrate and 2-(2-hydroxyphenyl) benzothiazolate. Then Zn(BTZ)2 was used as main light-emitting material doped with different amounts of fluorescent dye Rubrene and fabricated a series of white organic light emitting devices. The configurations were as follows: ITO/PVK:TPD/Zn(BTZ)2:Rubrene/Al. The doping concentration of Rubrene in Zn(BTZ)2 was 1.2%, 0.12%, 0.08% and 0.05%, respectively. According to the EL spectra and CIE coordinates of the above devices, the optimum doping concentration (0.05%, weight percent) had been determined. The steady and bright white light emitting of the device with 0.05% doping concentration had been obtained, and the white emission covered a wide range of driving voltage (10--22.5 V). The CIE coordinates were (x=0.341, y=0.334) at the driving voltage of 20 V, which was very close to the equi-energy point (x=0.333, y=0.333), and the corresponding luminance and external quantum efficiency were 4048 Cd/m^2 and 0.63% (4.05 Cd/A), respectively. Lastly, we also discussed the emitting mechanisms of the material and the devices.  相似文献   

13.
发展了毛细管电泳—安培检测方法,并将这一联用技术应用于苯酚、2,4-二氯苯酚、对硝基苯酚和邻、间、对甲酚的同时分离检测中.考察了氧化还原电位、缓冲溶液酸度、盐度、分离驱动电压及进样时间等因素对分析检测的影响.在优化实验条件下,以Na_2HPO_4-NaOH(pH11.38)为缓冲体系,6种酚类物质能够在25 min内实现基线分离,氧化还原电位0.78 V(versusSCE)下可以定量检测(三电极体系为:直径为300μm的碳圆盘电极、饱和甘汞电极及铂电极).实验结果表明,其线性达3个数量级(S/N=3),检测限达10(-7)mol/L.本文还尝试把该方法应用于两个实际工业污水的酚类污染物的检测,其回收率为94.0%~107.0%,结果令人满意.因此,该方法可为政府及企业环境检测部门提供一种快速、准确、低廉、无污染、重现性高的质量控制方法.  相似文献   

14.
利用反相液相色谱法(RP-HPLC)直接测定原料药中头孢拉定的含量.采用YQG-ODS色谱柱,以V(CH3OH)∶V(4%HAc-NaAc)=3∶7的溶剂作流动相,于λ=262 nm处紫外检测,以峰面积外标法定量.头孢拉定在0.027~0.29 g·L-1浓度范围内具有良好的线性关系,回归方程为Y(μV·s)=1.88×107X(g·L-1)+20 876,r=0.998 3,平均回收率为99.7%,RSD为0.57%(n=3).  相似文献   

15.
以甲胺、 氯乙酸钠、 氰酸钠等为原料, 用“一锅法”合成1-甲基海因, 合成总收率为62.9%.单晶经X射线衍射方法解析, 其晶体属于单斜 晶系, P21空间群, 其中a=0.558 9(3) nm, b=1.217 6(6) nm, c=0.809 0(4) nm;β=105.330(7)°;V=0.531 0(5) nm3;Z=4, Dc=1.427 mg/m3, μ=0.116 mm-1, F(000)=240.  相似文献   

16.
A new method is proposed for the preconcentration of vanadium(V) with crosslinked chitosan (CCTS) and determination by graphite furnace atomic absorption spectrometry (GFAAS). The adsorption rate of vanadium(V) by CCTS was 97% at pH 4.0, and vanadium(V) was eluted from crosslinked chitosan with 2 mL 2.0 mol·L−1 chlorhydric acid and determined by GFAAS. The detection limit (3σ,n=7) for vanadium (V) was 4.8×10−12g and the relative standard deviation (R.S.D) at concentration level of 2.6 μg·L−1 is less than 3.6%. The method shows a good selectivity and high sensity, and it was applied to determination of vanadium(V) in oyster and water samples. The analytic recoveries are (97±5)%. Biography: Wu Wei (1975-), female, Master candidate, research direction: environmental & analytical chemistry.  相似文献   

17.
We studied the luminescent and photovoltaic properties of poly(9,9-dioctylfluorene-co-bithiophene)(F8T2) based on ITO/PEDOT:PSS/F8T2/Bphen/LiF(0 or 1 nm)/Al and ITO/PEDOT:PSS/F8T2:PCBM/Bphen/Al.A stable and bright yellow emission was obtained from polymer F8T2,and the electroluminescence power reached 45 ?W at a 15 V driving voltage.Polymer F8T2 shows a broad absorption band from 400 to 500 nm,and has a shorter absorption edge at about 560 nm compared to that of the typical electron donor P3HT(650 nm).The photoluminescence quenching of F8T2 occurs with only a small fraction of blended PCBM due to the effective exciton dissociation at the interface between F8T2 and PCBM.Polymer solar cells(PSCs) using F8T2:PCBM as the active layer show a low power conversion efficiency(PCE) of 0.10% with an open circuit voltage(Voc) of 0.91 V and short circuit current density(Jsc) of 0.23 mA/cm2.The PSCs using F8T2:P3HT:PCBM as the active layer have a Voc of 0.85 V and Jsc of 3.02 mA/cm2,improving the PCE by about 0.90%.We attribute the improved cell performance to the higher number of photons harvested by P3HT molecules.  相似文献   

18.
人肺腺癌A549细胞广泛用于体外肺癌发病基因筛查、药物筛选等临床研究,低温保存是保持样本库中的A549细胞高质量的有效方法。本文针对A549细胞低温保存方法,通过使用非接触置核慢速降温程序减小降温过程中溶液的过冷度,并在此基础上优化保护剂乙二醇(ethylene glycol,EG)、二甲基亚砜(dimethyl sulfoxide,Me2SO)以及海藻糖的最佳浓度,通过检测复苏后肺腺癌细胞的回收率、细胞凋亡情况以及凋亡相关基因表达,对保存效果进行评估。实验结果表明,非接触置核慢速降温程序相比传统慢速降温程序可有效降低低温保护剂过冷度,并提高了细胞回收率。优化后最佳低温保护剂组合为7.5%(体积分数)Me2SO+2.5%(体积分数)EG+200 mmol 海藻糖,使用该保护剂低温保存复苏后的细胞回收率(91.59±1.51%)高于使用传统低温保护剂10%(体积分数)Me2SO的细胞回收率(86.72 ±1.86%),而且正常细胞比例高,可以很好地抑制细胞凋亡。  相似文献   

19.
A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chinese medicine, Loulu. The factors influencing separation performance were investigated and optimized. Under the optimal conditions, the contents of ecdysterone in Loulu were determined by HPLC system using MeOH-H2O (40∶60,V/V) as the mobile phase at a flow rate of 1.0 mL/min. The calibration curve was linear in the range of 0.5∼100 mg/L of ecdysterone concentrations. The detection limit of the analyte was 0.11 μmol/L (3σ) with a precision of 0.38% RSD (n=7,c=10.0 mg/L). The average recovery of the method was 98.7%. The proposed method has been applied to determine ecdysterone in practical samples, and the determined values by both external standard method and standard addition method were in good agreement. Compared to the traditional solid extraction method, the system proposed has the advantages of simple procedure, good reproducibility, minimum volume requirement, reduction of matrix interference and low contamination risk. Foundation item: Supported by Education Ministy Foundation for Chinese Returned Scholars and Nature Science Foundation of Hubei province (98J054). Biography: SHUAI Qin (1963-), famale, Ph.D. Candidate.  相似文献   

20.
0 IntroductionTrifluoperazine is a derivative of phenothiazine. It hasneuroleptic and antidepressive actions, hence has beenwidely used in the treatment of psychotic patients[1]. As it hassuch function and application, trifluoperazine’s characteristicsand detection methods were studied by means of spectropho tometry[2], capillary zone electrophoresis[3], titrimetry[4],fluorometry[5], high performance liquid chromatographyetc[6]. Because of the electroactivity of trifluoperaz…  相似文献   

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