长网多缸纸机“真空孔痕”纸病的解决

最近几年新上的长网多缸纸机，无论是复合压榨还是分部压榨，第一压区多数是真空压榨。真空压榨的优点是提高了纸机的车速；其缺点是真空系统通过真空辊眼孔对湿纸页的抽吸作用，纸面上或轻或重地均匀地留下了纤维被抽吸后聚结成团的痕迹，这不但影响了纸面的美观，而且也...     

卫生纸机压榨部运行参数及能效关系分析与优化

通过对纸机压榨部压力和压榨脱水原理的分析,得到出压榨部纸幅干度可作为压榨部的能耗指标,同时确定压榨线压力和纸机车速是压榨部能耗的主要影响因素。结合纸机实际生产测试并记录压榨脱水数据,绘制测试数据曲线图并拟合压榨线压力、纸机车速和出压榨部纸幅干度三者之间的函数关系,最终确定压榨线压力和纸机车速的最优取值范围。通过对测试数据的分析和拟合,控制压榨线压力在90 kN/m、纸机车速在1075 m/min时,纸幅质量可满足正常生产的要求,还可以节约2.1%的电能,实现卫生纸机压榨部的能耗优化。     

真空压榨痕的形成原因与防范措施

围绕1760mm纸机复合压榨在生产过程形成真空压榨痕纸病的原因进行分析,并就如何如何解决该纸病提出一系列相应的防范措施,从而达到消除纸病的目的。     

压榨部的运行对产品质量的影响

为了确保纸机能顺利和高效运行，压榨部必须无机械故障和纸幅断头，且能给干燥部提供干度高、强度好的纸幅。为了生产出优质产品，压榨部要尽量减小纸幅的粗糙度和两面性，避免纸幅压溃，皱褶或其他纸病。最后，还要尽量降低成本，如能耗、压榨毛布、真空、水和设备。压榨最重要的3个方面是：纸机运行性能、产品质量和工艺的经济性。这些方面比脱水性更为重要。本文描述了压榨对纸机的运行性能和产品质量的影响，并指出了如何避免那些负面影响。     

单网单缸纸机适应多品种生产的经验

我厂一台单网单缸纸机原来长期生产的品种为６０－１００克／米＾２单胶纸。随着市场经济的发展，为满足客户对多品种，低定量纸张的需求，我们对纸机压榨部进行了改进，并获得成功。减少了纸机断头，满足了低定量纸的生产要求。     

国产第二台1760／300新型传递压榨纸机投产

国产第二台１７６０／３００新型传递压榨纸机投产高家骅配套有引进机内门辊涂布机和软辊压光机的首台１７６０／３００新型传递压榨纸机，已于１９９１年底在南京纸厂试车出纸成功。尽管该机由于配套了国产模拟控制系统的电气传动存在速度不稳定的问题而影响生产，但从该...     

岳阳造纸厂胶印书刊纸技术改造工程的设计工作

本文介绍了岳阳造纸厂技术改造前~#1纸机的缺点和生产中存在的问题,以及技术改造的措施。引进的设备有意大利Beloit分公司的上浆系统,Converflo流浆箱,Bel-form成形器,Tri-vent复合压榨,4辊压光机和4150型复卷机。经过一年多的生产表明,这项技术改造是成功的,产品由凸版纸改为胶印书刊纸,产量由80t/d提高到130t/d,纸机效率达到85％,蒸汽消耗明显降低,经济效益显著。     

用K式复合压榨改造长网薄页造纸机

本文介绍了长网簿页纸机采用复合压榨提高产量、质量,增加经济效益的情况。     

1760／250长网纸机复合压榨

１７６０／２５０长网纸机的压榨是一种折角式排列的三辊双压区复合压榨，它的使用，为纸厂大量配比草浆生产较高级的文化用纸，提高车速，减少断头，改进成纸质量，起了重要的作用。本文详细地介绍了１７６０／２５０纸机复合压榨的结构原理、真空“影痕”的形成原理以及压榨的受力分析和中高计算，简要分析归纳出其特征，重点介绍了此压榨在文化用纸生产中的应用实践。     

解决压榨部粘辊断纸的措施

采用长网纸机以麦草纤维原料为主生产中高档文化用纸的厂家．常因浆料中细小纤维含量大，造成纸机压榨部粘辊断纸。因此常采用加大长纤维比例的办法来解决，但成本增加。近年来，许多厂家的纸机采用了宴会压榨（或将原普通压榨一压改复合压榨），姑辊断统现象有了很大改善。但就笔者在山东某厂参加1760长网多缸纸机（设计车速250～300m／min）生产低定量涂布原纸的情况来看，虽然纸机带有复合压榨，但压榨部的粘轨断纸现象仍然很严重，导致或机试产不正常。村级机各部的主要工艺多数进行了测试．结果如下：成浆打装反38SIt，纤维证重2．4已…     

立对高端造纸机的压榨织物技术策略-GOBEAR产品技术内涵

2009年中国的纸产量达到8640万t,规模居世界第一,各种最先进的纸机均已经在中国投产,目前中国的拥有世界上最宽的纸机,也拥有世界上最怏的纸机,中国的高速纸机水平也代表了国际高速纸机的水平。截止2009年,中国已经有高端造纸机264台。伴随着中国造纸业20年持续高速发展,作为造纸机的必须易耗品的压榨织物,近10年来,也取得了长足的进步与发展。面     

假性棉结初探

通过对织物上假性棉结形成原因,分布状况控制措施进行初步探讨,指出假性棉结对斜卡类织物的布面风格有较大影响,其形成原因是经纱与机件反复磨擦,改变了浮游纤维分布状态所致,在布面上的出现规律是斜卡类、经面锻纹类大于类织物;纯棉织物大于涤棉混纺织物,控制好因磨擦产生的毛羽增加率,合理配置工艺及维持适宜的温湿度,假性棉结可以得到有效控制。     

基于视觉图像识别的番茄表面农药残留量无损检测方法

为了提高对番茄表面农药残留量的准确检测能力,提出一种基于视觉图像识别的番茄表面农药残留量无损检测方法。采用激光成像技术进行番茄表面农药残留区域视觉图像采集,对采集的番茄表面图像进行农药残留量的光谱特征分析,提取番茄表面农药残留区域的边缘轮廓特征,根据特征提取结果进行番茄表面农药残留区域视觉图像重构,在重构的区域图像中采用分块匹配技术进行番茄表面农药残留量区域分割,结合自适应分块特征匹配方法实现番茄表面农药残留量检测识别。仿真结果表明,采用该方法进行番茄表面农药残留量的无损性较好,输出图像的信息饱和度较高,提高了对番茄表面农药残留量的准确检测能力,在番茄病虫害防治和农药的去除等方面具有很好的应用价值。     

High-quality forage can replace concentrate when cows enter the deposition phase without negative consequences for milk production

Mobilization and deposition in cows are different strategies of metabolism; hence, the aim was to study the possibility of reducing the crude protein (CP) supply during deposition to limit the use of protein supplements and minimize the environmental impact. A total of 61 Jersey and 107 Holstein cows were assigned to 4 mixed rations in a 2 × 2 factorial design with 2 concentrate to forage ratios (CFR) and 2 CP levels: high CFR (40:60) and recommended CP [16% of dry matter (DM); HCFR-RP], high CFR (40:60) and low CP (14% of DM; HCFR-LP), low CFR (30:70) and recommended CP (16% of DM; LCFR-RP), and low CFR (30:70) and low CP (14% of DM; LCFR-LP), where RP met the Danish recommendations. Cows were fed concentrate in an automatic milking unit. After calving, cows were fed HCFR-RP until entering deposition, defined as 11 kg (Jersey) or 15 kg (Holstein) of weight gain from the lowest weight after calving. Subsequently, cows either remained on HCFR-RP or changed to one of the other mixed rations. Comparing strategies during wk 9 to 30 of lactation showed higher dry matter intake (DMI) of mixed ration on HCFR compared with LCFR and on RP compared with LP. The DMI of the concentrate was higher on LCFR than on HCFR and higher on LP than on RP, resulting in overall higher DMI on HCFR and RP than on LCFR and LP. Crude protein intakes were higher on RP than on LP and starch intakes were higher on HCFR than on LCFR. Intakes of neutral detergent fiber tended to be higher on LCFR than on HCFR. Intakes of net energy for lactation were affected by CFR and CP level, with a higher intake on HCFR and RP than on LCFR and LP. No interactions were found between CFR and CP level for any feed intake variables. Yields of milk and energy-corrected milk were higher on RP than on LP, with no difference in yield persistency after the ration change. Milk composition did not differ among strategies but the protein to fat ratio was higher on HCFR than on LCFR and tended to be lower on RP than on LP. Differences in fatty acid composition were small, and de novo synthesis was high (>60%). Energy efficiency was higher on LCFR than on HCFR and no interaction with breed or parity was found. The N efficiency was higher on LP than RP, but with an interaction with breed due to lower N efficiency in Jersey than Holstein cows on HCFR-RP but higher N efficiency in Jersey than Holstein on LCFR-LP. In dairy production, concentrate in the mixed ration can be substituted with high-quality forage during deposition without negative effects on milk yield and composition when a sufficient CP level is ensured.     

Bacterial populations on teat ends of dairy cows housed in free stalls and bedded with either sand or sawdust

The main objectives of the experiment were: 1) to compare bacterial populations of mastitis-causing organisms on the teats of lactating dairy cattle housed on sand and sawdust bedding and, 2) to examine the relationship between bacterial counts present in the 2 bedding types with those on teat ends. Sixteen lactating Holstein cows were housed on either sand or sawdust-bedded free stalls using a crossover design with 3 wk per bedding type. Bedding samples were collected on d 0 (prior to animals lying on the bedding), 1, 2, and 6. Teat ends were sampled prior to the morning milking on d 1, 2, and 6. All samples were analyzed to determine coliform, Klebsiella spp., and Streptococcus spp. populations. There were 2 times more coliforms and 6 times more Klebsiella bacteria on teat ends of cows housed on sawdust compared with those housed on sand. In contrast, there were 10 times more Streptococcus spp. bacteria on teat ends of cows when housed on sand compared with sawdust. In both sawdust and sand bedding, coliforms, Klebsiella and Streptococcus counts increased over each experimental week, although patterns varied with bedding and bacteria type. Bacterial counts on teat ends were correlated with bacterial counts in sawdust (r = 0.47, 0.69, and 0.60 for coliforms, Klebsiella spp., and streptococci, respectively) and in sand (r = 0.35 for coliforms and r = 0.40 for Klebsiella spp.). In conclusion, coliforms and Klebsiella spp. on teat ends were more numerous when cows were housed on sawdust bedding, but Streptococcus spp. were more numerous on teat ends of cows housed on sand.     

基于百度指数的传统印染技艺公众关注度分析

以扎染技艺、蜡染技艺和蓝印花布印染技艺为研究对象,基于百度搜索指数分析公众对传统印染技艺的关注度。通过Holt-Winters模型进行序列分解,分析公众关注度的变化趋势和周期特点。结果表明:公众对扎染关注度逐年上升,对蜡染关注度在波动上升后几乎维持不变,对蓝印花布关注度在缓慢上升后有所下降,三者以年为周期波动的规律明显。SARIMA模型对三个序列的预测结果表明:扎染的公众关注度将持续增长,蜡染关注度将基本维持在原有水平,蓝印花布关注度将略有下降。文章从国家政策、人群分布、工艺特点等方面对两种模型所得结论进行解释分析,并给出合理化建议。     

果蔬贮藏保鲜产业现状、研究进展与科技支持

简要介绍了我国果蔬贮藏保鲜的现状,指出了当前果蔬贮藏的主要问题。论述了国内外有关果蔬贮藏保鲜的新技术及研究进展情况,包括:天然果蔬保鲜剂的研究、利用调压技术贮藏、臭氧及负氧离子保鲜、利用生物技术保鲜、静电场处理贮藏、低剂量辐射处理和紫外线处理保鲜以及细胞水结构化气调保鲜等国内外近几年发展起来的现代果蔬贮藏保鲜技术。并阐述了科技对我国果蔬贮藏保鲜产业的支撑作用。     

乌头总生物碱贴片皮肤安全性的研究

目的观察乌头总生物碱贴片对动物皮肤的毒性作用。方法用健康新西兰兔进行皮肤单次及多次给药刺激性实验;用健康豚鼠进行皮肤过敏性实验。结果乌头总生物碱贴片中剂量组单次给药时未见对新西兰兔完整皮肤有刺激性反应,对破损皮肤有轻度刺激性;多次给药对兔完整皮肤无刺激反应,对破损皮肤有中度刺激反应。但停药后刺激反应消失,皮肤恢复正常。乌头总生物碱贴片中剂量组对豚鼠完整皮肤无致敏作用。结论乌头总生物碱贴片皮肤局部用药有较好的安全性,为临床应用提供了安全性保证。乌头总生物碱贴片的处方合理,制备工艺可靠。     

饮料主剂生产中的质量控制

对饮料主剂生产的质量控制，例如进料控制、过程控制、成品控制、不合格品控制以及产品标识和可追溯性控制等进行了论述。     

基于相对总变差模型与自适应形态学的织物瑕疵检测

为解决目前基于图像处理的织物瑕疵检测算法中,因织物纹理的多样性与瑕疵形状尺寸的不确定性所造成的检测效果差的问题,提出一种基于结构-纹理模型与自适应数学形态学的织物瑕疵检测算法。首先采用相对总变差模型对织物图像进行滤波以去除织物纹理,然后在得到的灰度图像上直接进行基于自适应邻域的灰度形态学运算,形态学算子采用开运算算子,最终得到织物瑕疵的增强图像。采用基于相对总变差模型与自适应形态学相结合的方法与2种已知的Gabor算法进行比对,对4类典型织物瑕疵进行检测实验和分析。结果表明,本文方法能更好地提取出织物瑕疵。