有机酸法玉米秸秆皮浆短流程TCF漂白特性

选择短流程漂白技术对有机酸法玉米秸秆皮浆(OABCSRP)进行漂白,研究了碱处理(E)、压力H2O2(PO)和H2O2(P)及其组合漂白工艺对OABCSRP浆特性的影响。结果表明,碱处理对OABCSRP浆脱木素选择性高,是后续漂白的重要基础,当用碱量4.0%时,浆的得率为95.4%、脱木素率为23.5%、黏度为115 mPa.s、亮度为44.2%;短流程E(PO)漂白可作为中高白度文化用纸浆料的漂白,在E段用碱量4.0%、PO段H2O2用量为2.0%时,可获得得率87.6%、黏度53.5 mPa.s、亮度79.9%的漂白浆,E(PO)漂白浆具有较好的打浆和纸张性能;短流程E(PO)P漂白在H2O2总用量为2.5%时,可获得得率为86.4%、黏度为59.6 mPa.s、亮度为82.7%的漂白浆。

有机酸法玉米秸秆皮浆短流程TCF漂白特性

为寻求环境友好的有机酸法玉米秸秆皮浆的短流程漂白程技术，研究了碱处理（E）、压力过氧化氢（P0）和过氧化氢（P）及其组合漂白工艺对有机酸法浆特性的影响。结果表明：碱处理对有机酸法浆脱木质素选择性高，是后续漂白的重要基础，当用碱量4．0％时，浆料得率为95．4％、脱木质素率为23．5％、黏度为115mPa·s、白度为44．2％ISO：用短流程E（PO）漂白程序，在E段用碱量4．0％、（PO）段H202用量为2．0％时，可获得得率87．6％、黏度53．5mPa·8、白度79．9％ISO的漂白浆，E（PO）漂白浆具有较好的打浆和纸张性能；用短流程E（PO）P漂白程序，在H2O2总用量为2．5％，可获漂白浆得率为86．4％、黏度59．6mPa·s、白度82．7％ISO的纸浆。

几种非木材原料有机酸法分离纤维的造纸特性研究

基于制浆造纸与生物质精炼联合发展的理念,以经过有机酸处理后剩余的原浆(竹片原浆、芦苇原浆、玉米秸秆原浆、蔗渣原浆)为研究对象,通过测定四种非木材纤维原浆的化学组成、纤维形态和成纸性能,对每种原浆的造纸性能进行评估。实验结果表明,有机酸对四种原料的木素溶出率(85~88%)和半纤维素溶出率(72~86%)均较高,而灰分的脱除率较低;在四种原浆中,芦苇原浆和竹片原浆的纤维素含量较高,纤维长度和长宽比较大,纤维均一性较好,且纤维弯曲及扭结比例较小,表现出较好的纤维性能;另外,芦苇原浆和竹片原浆的抗张、耐破、环压和挺度均较美废浆高,表现出优良的的成纸性能;蔗渣原浆通过将其与长纤维浆混合,可显著提高配抄纸页的强度。

有机酸法生物质炼制原浆的造纸性能研究

以有机酸法生物质炼制过程副产物--桉木原浆为研究对象,通过测定桉木原浆的化学组成、纤维形态、打浆性能和成纸性能,对桉木原浆纤维的造纸性能进行评估。研究结果表明,相对于阔叶木KP浆,桉木原浆中纤维素含量较高,但半纤维素含量过低,打浆时纤维易切断,打浆度上升较快,不利于纤维层间结合力的提升;桉木原浆的纤维重均长度、长宽比和纤维强度均低于阔叶木KP浆和美废浆,影响了成纸的撕裂性能。另外,桉木原浆的纤维弯曲指数和扭结比例较低,细小纤维含量较高,使得桉木原浆的抗张强度、耐破强度和环压强度较好,适宜抄造瓦楞芯纸等包装用纸,可代替美废浆用于抄造对撕裂度要求不高的纸种。

有机酸修饰溶胶/凝胶法制备的二氧化钛纳米薄膜的表征

采用有机酸表面修饰法 ,通过钛酸四丁酯的可控水解制备了油酸修饰的TiO2 纳米微粒 ,并在此基础上采用提拉法制备了锐钛型TiO2 纳米薄膜 .利用FR -IR光谱、Raman光谱、紫外 -可见光谱、SEM等手段进行了表征 .

Determination of Five Organic Acids in Radix Isatidis by Column Partition Chromatography and Capillary Zone Electrophoresis柱分配色谱-毛细管区带电泳联用分析板蓝根中五种微量有机酸(英文)

Aim To determine five organic acids in Radix Isatidis . Method The extraction method and the column partition chromatographic conditions were studied. Then a capillary zone electrophoretic method was set up for the determination. Results The linear ranges of quinazolinone acid, n anthranilic acid, benzoic acid, salicylic acid, and syringic acid were 5 52-92 0 μg·mL -1 , 5 12-102 μg·mL -1 , 2 28-84 4 μg·mL-1 , 4 78-159 μg·mL -1 , and 1 74-87 0 μg·mL -1 respectively. Conclusion The established method is accurate and simple.

有机溶剂制浆技术进展

本文介绍了几种主要的有机溶剂制浆方法 ,评价了方法的优点。

Determination of Organic Acids in Root Exudates byHigh Performance Liquid Chromatography: III. Effectsof Interfering Factors

A solution culture experiment was conducted to investigate the effects of collection time and interferingions on separation and determination of low-molecular-weight organic acids in root exudates of soybeanusing the method for directly collecting root exudates. The suitable collection time of root exudates andthe interfering ions affecting organic acid determination were determined. The method for removing theinterfering ions was established and analyzed. The release amount of root exudates increased with theincrease of collection time from 0 to 120 min but decreased with increasing of collection time from 120 to 240min. The maximum exuding amounts of organic acids were observed in root exudates at the collection time of120 min. There was a significant difference of organic acid components between the treatments of collectiontime of 120 min and 240 min. Citric acid was found only in the treatment of 120 min collection time. NO3-was the main interfering ion in organic acid determination and had the same retention time as oxalic acid.Anion exchangs resin (SAX) properly treated by HPLC (high performance liquid chromatography) solventcould remove NO3- anion in sample solution of root exudates, thus enhancing the recoveries of organic acidsin root exudates. There was no significant effect of the chemicals added into sample solution such as H3PO4,SAX and KNO3 on the retention time of organic acids.

Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I. Development and Assessment of Chromatographic Conditions *1

Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids.

Enrichment of Semi-Volatile Organic Acids from Aqueous Solutions by Multiple-Effect Membrane Distillation

Multiple-effect membrane distillation （MEMD） process for enriching semi-volatile organic acids from their individual aqueous solutions was performed by using a hollow fiber-based air gap membrane distillation （AGMD） module with the function of internal heat recovery. Aqueous solutions of glyoxylic acid, glycolic acid, lactic acid, pyrnvic acid, malonic acid and glutaric acid were used as model feed. For a feed of 1% （mass fraction）, each acid could be enriched for 8--20 times, which depended on the surface tension of the concentrate. The operation performance of MEMD process was characterized by permeation flux J, performance ratio PR and acid rejection rate R. The effects of cold feed-in temperature, heated feed-in temperature, feed-in volumetric flow rate and feed-in concen- tration on MEMD performance were experimentally evaluated. Maximum values of J, PR and R were 4.8 L/（h-m2）, 9.84 and 99.93%, respectively. Moreover, MEMD process demonstrated a fairly good stability in a long-term experiment lasting for 30 d when aqueous solution of 4% （mass fraction） lactic acid was used as a feed.

Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography:Ⅱ.Influence of Several Testing Conditions

Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatography (HPLC) with a wavelength of UV (ultraviolet) 214 urn and a mobile phase of 18 mmol L-1 KH2PO4 buffer solution (pH 2.1). The thermal stability of organic acids was determined by comparing the recoveries of organic acids in different temperature treatments. The relationships between column temperature, flow rate or solvent pH and retention time were analyzed. At low solvent pH, separation efficiency of organic acids was increased by raising the flow rate of the solvent because of lowering the retention time of organic acids. High column temperature was unfavorable for the separation of organic acids. The separating effect can be enhanced through reducing column temperature in organic acid determination due to increasing retention time. High thermal stability of organic acids with low concentrations was observed at temperature of 40 ℃-45℃. Sensitivity and separation effect of organic acid determination by HPLC were clearly improved by a combination of raising flow rate and lowering column temperature at low solvent pH.

Organic acids and inorganic anions in Bayer liquors by ion chromatography after solid-phase extraction

A method for the simultaneous separation and determination of organic acids and inorganic anions in Bayer liquors was developed by gradient ion chromatography with suppressed conductivity detection. Formate, acetate, propionate, oxalate, succinate, glutarate, fluoride, chloride and sulfate were separated and determined in 33 min. The samples were pretreated with solid-phase extraction, which has high selectivity for removing a large number of metallic ions in the Bayer liquors, and filtered with a 0.45 μm filter membrane before being injected into the ion chromatographic system. The separation of six organic acids and three inorganic anions was achieved on an IonPac AS11-HC column with KOH as the eluent, and the detection was performed by a conductivity detection mode. No interference is found in the presence of fluorate, chlorate and sulphate when organic acids are determined. The calibration graphs of peak area for all the analytes are linear over a wide range. The relative standard derivation of the peak area of analytes is less than 2.14%. Under optimum conditions the detection ranges from 0.2 to 100.0 mg/L. The average recoveries of the added standards are between 94.3% and 102.8%.

Synthesis of glycerine-xanthate and its depressing mechanism in separation of marmatite from arsenopyrite

A small molecular organic depressor glycerine-xanthate was synthesized. The effect of glycerine-xanthate on the flotation of sulfide minerals was investigated based on a function of pH value and concentration of glycerine-xanthate through flotation experiments in the presence and absence of Cu^2＋. The results show that glycerinee-xanthate has a strong dressing effect on marmatite at pH〉6 and on arsenopyrite in weak acid and base conditions with butyl-xanthate as collector. In the presence of glycerine -xanthate, marmatite is activated by addition of Cu^2＋, but arsenopyrite cannot be activated and remains unfloatable. So the selective separation can be achieved for two minerals. The depression of glycerine-xanthate on sulfide minerals was discussed based on the radical electronegative calculation and the theory of HSAB. Infrared spectrum shows that there are some -OH and-CSS-in glycedne-xanthate molecule, which competes with butyl-xanthate on the mineral surface. As a result of many hydrophilic groups in glycerine-xanthate, the surfaces of marmatite and arsenopyrite become hydrophilic, thus the flotation of marmatite and arsenopyrite is depressed. The collector is adsorbed preferentially on the surface of marmatite and it shows a better floatability in the presence of Cu^2＋, whereas, the surface of arsenopyrite absorbs glycerine-xanthate and the flotation of arsenopyrite is depressed by glycerine-xanthate.

Cluster Analysis of Polyphenols and Organic Acids in 11 Different Brand Cigarette Samples at Home and Abroad

The objective of this research was to investigate the differences between local cigarette and foreign cigarette and supplied a base for improving the quality of cigarette. Different kinds of polyphenols and organic acids in 11 different brand cigarette samples at home and abroad were classified by the method of cluster analysis. The results indicated that the 11 samples could be classified into 2 classes. Suyan, Furongwang, Chinese, Baisha, Dihao, Yunyan, Hongtashan belonged to type 1; foreign cigarettes that represented by Marboro, Blue pacific and Brazil cigarette belonged to type 2. The content of malic acid and citric acid in type 1was higher than type 2, the content of malonic acid was higher in type 2, and there is no difference between the type 1 and type 2 about the content of polyphenols. In conclusion, the content of malic acid and citric in Chinese cigarettes was higher than foreign, but the content of malonic acid was lower than foreign. There is no difference between Chinese cigarettes and foreign cigarettes about the content of polyphenols.

Cloning, Expression and Characterization of a Lipase Gene from Marine Bacterium Pseudoalteromonas lipolytica SCSIO 04301

Absract A lipase gene, 1ip1233, isolated from Pseudoalteromonas lipolytica SCSIO 04301, was cloned and expressed in E. coli. The enzyme comprised 810 amino acid residues with a deduced molecular weight of 80kDa. Lip1233 was grouped into the lipase family X because it contained a highly conserved motif GHSLG. The recombinant enzyme was purified with Ni-NTA affinity chro- matography. The optimal temperature and pH value of Lip1233 were 45 ℃ and 8.0, respectively. It retained more than 70% of origi- nal activity after being incubated in pH ranging from 6.0 to 9.5 for 30min. It was stable when the temperature was below 45℃, but was unstable when the temperature was above 55℃. Most metal ions tested had no significant effect on the activity of Lip1233. Lip1233 remained more than original activity in some organic solvents at the concentration of 30% （v/v）. It retained more than 30% activity after incubated in pure organic solvents for 12 h, while in hexane the activity was nearly 100%. Additionally, Lip 1233 exhib- ited typical halotolerant characteristic as it was active under 4M NaC1. Lip1233 powder could catalyze efficiently the synthesis of fructose esters in hexane at 400C. These characteristics demonstrated that Lip1233 is applicable to elaborate food processing and organic synthesis.

Presence of carboxylate salts in marine carbonate strata of the Ordos Basin and their impact on hydrocarbon generation evaluation of low TOC, high maturity source rocks

The total organic carbon （TOC） in the marine source rock of the Ordos Basin mostly ranges from 0.2% to 0.5%. The industrial standard commonly states that the TOC value has to be no less than 0.5% （0.4% for high mature or over-mature source rock） to form large petroleum reservoirs. However, gas source correlation indicates that the natural gas in the Jingbian gas field does receive contribution from marine source rocks. In order to determine the effect of Carboxylate salts （or called as organic acid salts） on TOC in highly mature source rocks with low TOC value, we sampled the Ordovician marine source rock and the Permian transitional facies source rock in one drilled well in the southern Ordos Basin and performed infrared and GC-MS analysis. It is found that both kerogen-derived organic acids and carboxylate salt-conversed organic acids exist in both marine and transitional facies source rocks. The carboxylate salt-conversed organic acids mainly come from the complete acidification of carboxylate salts, which confirms the presence of carboxylate salts in the marine source rocks. Although the C16：o peak is the main peak for the organic acids both before and after acidification, the carboxylate salt-conversed organic acids have much less relative abundance ahead of C^6：o compared with that of the kerogen-based and free organic acids. This observation suggests that the kerogen-based and free organic acids mainly decarboxylate to form lower carboxylic acids, whereas the carboxylate salt-conversed organic acids mainly break down into paraffins. By using calcium hexadecanoate as the reference to quantify the kerogen-derived and carboxylate salt-conversed organic acids, the high TOC （〉2.0%） marine source rocks have low carboxylate salt content and the low TOC （0.2%-0.5%） marine source rocks contain high content of carboxylate salt. Therefore, for the marine source rocks with 0.2%-0.5% TOC, the carboxylate salts may be a potential gas source at high maturity stage.