基于动态聚类算法的CWNN在纸张紧度检测中的应用

针对造纸生产线中纸张紧度无法在线检测的问题,利用小波-神经网络的分析和非线性逼近能力拟合纸张紧度J与纸张定量Q、纸张水分M、叩解度°SR、纸浆纤维湿重g、浆速网速比KT等可在线检测量间的非线性关系.通过K均值聚类算法预处理训练样本以平滑优化途径,解决连续小波神经网络(CSNN)的局部极小化问题.将学习算法中的主要系数独立地分配到网络的权值和小波尺度因子中,以提高网络的并行运算能力和收敛速度.训练好的CSNN用于纸张紧度的在线检测.仿真和实践表明:该方法测得的纸张紧度精度高.     

微纤化纤维素-填料复合体在纸张增强/加填上的应用研究

自制的微纤化纤维素-填料复合体(T-MFC)是一款将钛白粉和微纤化纤维素(MFC)结合在一起的产品,将其加入到纸张抄造中,探究在纸张增强以及填料留着方面的应用效果.实验结果显示,T-MFC的分散程度越好,增强效果越好;T-MFC的添加量为5％(质量分数)时,纸张的综合物理性能最佳,可以在提高纸张灰分的同时,不降低纸张强度;通过添加T-MFC,在降低定量后,纸张的各项物理性能均不降低.     

壳聚糖季铵盐交联酰胺共聚物的制备及应用

以羟丙基三甲基氯化铵壳聚糖(CC)为阳离子单体,甲基丙烯酸缩水甘油酯(GMA)作交联剂,二乙烯三胺和己二酸为原料,通过水溶液共聚法制备了壳聚糖季铵盐交联酰胺共聚物(CC-GPPC)。通过IR、SEM、TG、GPC对其结构性能进行表征；探讨了CC和GMA及DETA对CC-GPPC的性能及其浆内添加后纸张物性的影响。结果表明：在CC添加量为1.0g,AA:DETA:GMA的摩尔比为1:1.1:0.9时, 可制得性能较为优越的壳聚糖季铵盐交联酰胺共聚物CC-GPPC,此时聚合物溶液分子量为74520,平均粒径795 nm,分散指数0.581,常温下可稳定储存60d以上,当CC-GPPC的浆内添加量为绝干浆的0.6%时,纸张干抗张指数为52.99 N.m/g,湿抗张指数为16.82 N.m/g,与原纸相比,纸张干、湿抗张指数分别提高了29.8%、80.7%,纸张增湿强性能明显提高,与商用PAE湿强树脂相比,达到了无氯且性能优越,纸张湿抗张指数增加了10.6%,是一种绿色环保型纸张增湿强剂。     

不同纸张对数字输出阶调特性的影响

为了了解不同纸张对数字输出阶调特性的影响,采用CorelDraw软件制作单色色阶测试版,选择常用的普通打印纸、一般照片纸和光泽照片纸在Epson Stylus Photo R250彩色喷墨打印机上进行输出,用DS分光光度仪对输出色阶进行CIEL*a*b*色度值的测量,用色彩管理软件为不同纸张制作特性文件,对不同纸张所能达到的数字输出阶调特性进行定量分析。针对选用的纸张进行测量后得出结论,输出色彩丰富的图像优选的纸张应是光泽照片纸,输出灰度层次丰富的图像可以选择普通打印纸。     

与食品接触的再生纸毒性检测和化学分析

与食物接触的材料，包括纸张，必须符合有关安全的基本标准。这意味着纸张与食物的接触不应引起成分的迁移，从而危害人体健康。本研究对不同品质纸张进行初步测评他们的安全适用性,评估的纸和纸板的体外毒性试验筛选。通过化学分析和不同的体外毒性测试系统对提取物进行了检查。产品测试不同原料或不同制造工艺纸张。用99%乙醇或水提取纸张产品样品，对提取物中可能的迁移物进行了定量鉴定。     

新闻纸轻量化的功能助剂——水合硅酸的研制

降低新闻纸定量为了节约木材原料，增加印刷使用面积，也是世界性的必然发展趋势。本工艺采用水玻璃和硫酸中和反应，经水洗、均质化处理，制备出水合硅酸料浆。经天津造纸研究所试用表明：水合硅酸具备降低纸张定量，提高纸张不透明度和强度的作用，满足印刷行业的需求。     

造纸用脲醛树脂分散液白色颜料申请专利

Ciba-Geigy公司研制成一种造纸用脲醛树脂分散液,其游离醛含量<0.1％,含15％～35％的1.25～1.4:1甲醛-尿素树脂,比表面积5～30m~2/g,孔体积2～4ml/g,平均粒径0.05～1μm,平均附聚体尺寸(A)3～10μm。在树脂的制备过程中用氨基磺酸作胶凝剂。将该分散液用作纸张填料(如定量为50g/m~2的     

纸张用有机硅抗水剂的制备

采用氨基硅油、十二烷基三甲氧基硅烷、甲基三乙氧基硅烷配成11种抗水剂,用于纸张的抗水处理.通过渗透法和接触角法测试发现,有机硅抗水剂对实验选择的9种纸张均有明显的抗水效果;其中采用氨基硅油配制的抗水剂效果最好,经其处理的生宣纸与空白样相比,接触角由完全润湿提高到125°,渗透时间由0提高到18 s.最佳应用工艺为:将氨基硅油配制成质量分数为2.041%的甲苯溶液,按照10g/m2的涂布量喷涂于纸张表面,自然晾干3～5天至恒定质量.     

新闻纸轻量化的功能助剂-水合硅酸的研制

采用水玻璃和硫酸中和反应，经水洗、均质化处理，制备出水合硅权料浆。经试用表明：水合硅酸具备降低纸张定量，提高纸张不透明度和强度的作用，满足印刷行业的需求。     

TEMPO氧化纳米纤维素的制备及其对纸张性能的影响

以漂白桉木浆和废报纸为原料,利用2,2,6,6-四甲基哌啶-1-氧自由基(TEMPO)/NaBr/NaClO氧化体系对其进行处理制备氧化纳米纤维素,并探究两种氧化纳米纤维素添加量对纸张性能的影响。研究结果表明:桉木浆氧化纳米纤维素的平均纤维长度约为75~95 nm,长径比约为6.5~8.5,均高于废报纸氧化纳米纤维素(45~75 nm,4~6)。添加桉木浆氧化纳米纤维素和废报纸氧化纳米纤维素均可使纸张抗张指数、耐破指数和撕裂指数增加。添加6%桉木浆氧化纳米纤维素时,纸张抗张指数由21.16(N·m)/g增加至31.37(N·m)/g,耐破指数由1.32(kPa·m^(2))/g增加至1.84(kPa·m^(2))/g,撕裂指数由6.61(mN·m^(2))/g增加至8.03(mN·m^(2))/g;添加6%废报纸氧化纳米纤维素时,纸张抗张指数由21.16(N·m)/g增加至27.22(N·m)/g,耐破指数由1.32(kPa·m^(2))/g增加至1.79(kPa·m^(2))/g,添加4%废报纸氧化纳米纤维素,纸张撕裂指数由6.61(mN·m^(2))/g增加至8.12(mN·m^(2))/g,可见,添加桉木浆氧化纳米纤维素效果更佳。添加1%阳离子淀粉,有助于两种氧化纳米纤维素对纸张强度的提高,其中桉木浆氧化纳米纤维素可使抗张指数最大提高51.09%,耐破指数提高50.00%,撕裂指数提高27.62%。     

MD-CD interaction modeling and control of paper machines

For better quality control of paper machines, variations in the machine direction (MD), cross-machine direction (CD) and their inherent interactions should be minimized. In this paper, a dynamic MD-CD interaction model is developed by relating the effect of MD dry basis weight to the CD profile. Based on this model, a combined MD-CD generalized predictive control strategy is proposed to handle the strong MD-CD interaction. A set of industrial data was used to identify the interaction model. Results from closed-loop simulation of the interaction model under the proposed control strategy show that a significant improvement in CD control during a grade change can be achieved.     

微波辐射甘蔗渣制造活性炭的试验研究

以ZnCl2为活化剂，采用微波辐射甘蔗渣制备活性炭，研究了微波功率、活化时间、ZnCl2用量与甘蔗渣质量比、干燥功率对活性炭性能的影响。试验的最佳反应条件：ZnCl2与甘蔗渣质量比为2．5：1．0、炭化及活化微波有效功率为35W／g（甘蔗渣，干重）、炭化及活化时间为25min、干燥有效功率为12W／g（活性炭，干重）。在上述条件下制得的活性炭的比表面积为1250m^2／g以上。     

产烃葡萄藻在气升式光生物反应器中的分批补料培养

在3 L气升式光生物反应器中进行了产烃葡萄藻的培养. 批式培养时，葡萄藻消耗氮、磷的速度较快，培养液中氮、磷营养盐的缺乏限制了藻细胞进一步生长和增殖. 采取分批补料方式，使培养液中KNO3和K2HPO4浓度分别维持在100和30 mg/L，可克服氮、磷限制问题. 与批式培养相比，生物量从1.3 g/L增加到1.9 g/L，烃含量从占细胞干重的22%提高到29%，从而使烃产量从0.286 g/L增加到0.551 g/L，提高了92.6%.     

Production of bacterial cellulose by a static cultivation using the waste from beer culture broth

Bacterial cellulose (BC) was produced by using the waste from beer culture fermentation instead of a chemically defined medium. Static cultivation was superior to the shaking cultivation on the basis of the BC production. The amount of BC produced during 120 hrs of cultivation using the waste from beer fermentation broth (WBFB) by a static cultivation was 4.52 g/L on the dry weight basis and much higher than 0.45 g/L produced from a Buffered Schramm and Hestrin (BSH) chemically-defined medium. The addition of 1% industrial-grade glucose to WBCB increased the production of bacterial cellulose from 8.46 to 13.95 g/L after 336 hrs of cultivation. Water soluble oligosaccharide (WSOS), the by-product obtained during BC cultivation increased to 5.05 g/L at 192 hrs of cultivation and then decreased to 2.18 g/L at 336 hrs. This work was presented at 13 ^th YABEC symposium held at Seoul, Korea, October 20–22, 2007.     

Synthesis of an elastic β‐cyclodextrin hydrogel cage by hydroxyethyl cellulose

Current cyclodextrin (CD) hydrogels have disadvantages, including a limited CD content, long reaction time, and complicated chemical reactions. To overcome these, a one‐pot reaction was adopted, and a concept of a β‐CD hydrogel cage was proposed. Hydroxyethyl cellulose (HEC) was used as the raw material with the adjustment of the stoichiometric relationship among the crosslinking agent of epichlorohydrin, alkali environment, and β‐CD amount, and an elastic β‐CD hydrogel cage system was established. After the β‐CD was caged, the contents of active β‐CD in hydrogel products reached 74.45 and 69.14 wt % by weight measurement and photometric titration, respectively. Furthermore, compared to the pure HEC hydrogel, the hydrogel mechanical strength improved obviously after the β‐CD was caged, and we obtained a faster water swelling rate at the same time. Finally, a hydrophobic molecule of phenolphthalein (PP) was used to evaluated the activity of caged β‐CD in the hydrogel. In addition, the absorption and release of PP by an elastic β‐CD hydrogel cage at certain time intervals were also studied. The results demonstrate that the β‐CD hydrogel cage was used as a functional molecule carrier to quickly absorb and sustain the release of PP. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44388.     

超声波法提取山竹皮中总黄酮的研究

为获取山竹皮中总黄酮的最佳提取工艺,采用超声波提取法对山竹皮总黄酮进行提取,以芦丁为标准品,在波长500 nm处测定吸光度,得回归方程Y=0.010 9 X-0.027 8 (r=0.997 8).实验考察ω(乙醇)、料液比、提取时间、溶剂类别对山竹皮中总黄酮提取率的影响.在此基础上,采用正交实验设计用L9 (34)优...     

丙烯酰胺与甲基丙烯酰氧乙基三甲基氯化铵双水相共聚临界相分离研究

在聚乙二醇（PEG）水溶液中进行丙烯酰胺（AM）与甲基丙烯酰氧乙基三甲基氯化铵（DMC）的双水相共聚。用分光光度计在线检测双水相聚合过程中体系透光率变化,确定了分相点并用改进溴化法测定了临界转化率,研究了反应条件对临界转化率的影响。引发剂用量或温度变化对临界转化率影响不大;单体用量、PEG用量或PEG分子量增加,临界转化率下降;DMC比例增加时,临界转化率增大。用凝胶渗透色谱法（GPC）测定了临界分子量,发现引发剂用量增加、温度升高或DMC比例增加,均使临界分子量减小;总单体用量或PEG用量增加,临界分子量先增大后减小;而PEG分子量增大增加时,临界分子量随之增大。     

水溶性偶氮引发剂引发丙烯酸钠的反相乳液聚合反应

采用水溶性偶氮引发剂V50和NaHSO3组成的复合引发剂,通过反相乳液聚合制备了相对分子质量高的聚丙烯酸钠。研究了引发剂种类及用量、乳化剂的HLB值及其用量、反应温度等因素对聚丙烯酸钠相对分子质量的影响规律。并采用正交优化方法对聚丙烯酸钠的聚合反应工艺进行优化研究。结果表明:复合引发剂V50/NaHS03效果优于APS/NaHSO3。最佳聚合工艺条件为复合乳化剂的用量为9%(占油相的质量百分数)、其HLB值为5.7、单体中和度为90%、引发剂用量为2.0%(占单体的质量百分数)、反应温度为40°C。在最佳反应条件下,得到的聚合物相对分子质量可达到2.1×107,溶解时间23 min(0.3 g/100 g H2O,45°C)。     

Studies on ultrafiltration of spent sulfite liquor using various membranes for the recovery of lignosulphonates

Concentration and purification of lignosulphonates (LS) present in spent sulfite liquor (SSL) obtained from the paper industry were carried out through ultrafiltration (UF). The salts of lignosulphonic acid, a product of acid hydrolysis of lignin, are a major component of technical LS. In respect of molecular weight composition, LS represent a polydispersed system with a wide range of molecular weight distributions, from 200 to 150,000 Da. They have good adhesive properties and are used as plasticizers, peptizers, and stabilizers in the industry. The usefulness of LS is dependent on the molecular weight composition. Higher molecular weight LS fractions show properties of amorphous polymeric substances, which may have much industrial use. Diafiltration operation was used for purification of LS. The LS present in SSL were estimated using different membranes (polysulphone, cellulose acetate, fluoropolymer) of varied cut-off sizes (1 K, 5 K, 10 K, 20 K, 25 K, 50 K and 100 K). Sharp cut-off membranes in between 20 K and 100 K Da show close rejections (80-84%). The effect of different operating conditions such as different transmembrane pressures, dilution of SSL, membrane materials and different cut-off sizes was studied on flux and rejection. The effect of sharp and diffused cut-off membranes on flux and rejection was also studied. Continuous diafiltration (CD) was conducted over a high MWCO membrane (GR100K). It was observed that CD with a sharp cut-off membrane gave steady flux and a very good rejection of LS.     

4,4'-二羟基二苯砜合成新工艺的研究

对苯酚磺化、脱水法合成4,4'-二羟基二苯砜（BPS）工艺进行改进。研究了使用新的催化剂（2,6-萘二磺酸）和溶剂（均三甲苯-均四甲苯混合溶剂）,提高经苯酚和浓硫酸合成BPS的收率和纯度。详细研究了合成过程中所用溶剂类型及混合溶剂比例、催化剂种类及用量对BPS收率、纯度及异构体2,4'-二羟基二苯砜变化规律的影响。较好的工艺条件为：100 g均三甲苯-均四甲苯混合溶剂（二者质量比3∶1）,5 g 2,6-萘二磺酸催化剂,98.5 g苯酚,在110 ℃将51.2 g硫酸滴加完成后,将反应液快速升温至回流温度172 ℃并保持5 h。BPS产品收率可达99.3%,纯度为96.49%。该方法收率高,催化剂便宜,易于工业化。