超微化雷竹笋膳食纤维对火腿肠品质的影响

为了研究超微化雷竹笋膳食纤维(dietary fiber,DF)对火腿肠品质特性的影响,将2%和4%(以100 g猪肉计)三种粒径(DF1:(177.82±6.25) μm、DF2:(19.87±1.76) μm、DF3:(8.89±0.45) μm)的膳食纤维应用于火腿肠的制作工艺中。采用感官评价、质构分析、低场核磁共振等方法对新型火腿肠进行综合评价。结果表明:添加4% DF3 的火腿肠的持水力最大为90.28%±0.54%,与对照相比提高8.50%,膳食纤维能显著提高火腿肠的持水性(p<0.05);添加2% DF3 的火腿肠的硬度及咀嚼性下降,但弹性、黏聚性及凝胶强度增强;低场核磁共振中显示新型火腿肠中的水分向快迟豫(即水分结合紧密的方向,T_2时间短的方向)方向移动,结合水比例增加、自由水比例减少更有利于火腿肠储藏;添加2% DF3 的新型火腿肠的色差及感官评分与对照组不存在显著性差异,不影响产品销售。综上可知,2% DF3 是制备新型火腿肠的最佳选择。

基于Weibull分布的超短微丝钢纤维增强混凝土冲击寿命分析

为了研究超短微丝钢纤维增强混凝土的抗冲击性能,采用改进的落锤冲击试验装置,对24块直径150 mm,厚度63 mm的圆饼形试块进行了冲击试验,对比分析了超短微丝钢纤维混凝土的冲击破坏形态、钢纤维体积掺量对超短微丝钢纤维混凝土冲击性能的影响和增强机理。同时,基于Weibull分布理论对纤维掺量的超短微丝钢纤维混凝土初裂和终裂冲击次数进行了拟合分析和寿命估计。结果表明:超短微丝钢纤维掺量从0.8%增加到1.2%能提高纤维混凝土抗冲击性能;两参数Weibull分布能较好的描述超短微丝钢纤维混凝土抗冲击次数的分布规律;在不同的失效概率下,超短微丝钢纤维混凝土的冲击寿命估计值与试验所得结果的增长趋势性基本保持一致。

超微粉碎-纤维素酶法改性竹笋膳食纤维的工艺评价

以竹笋为原料,评价超微粉碎-纤维素酶法对膳食纤维(DF)改性的影响。通过检测竹笋可溶性膳食纤维(SDF)的得率、持水力以及膨胀力,分析超微粉碎法粉碎时间(0~25 s)、纤维素酶浓度(0.1%~0.5%)、酶解时间(30~150 s)、酶解温度(30~55℃)、pH值(4.5~5.5)对竹笋膳食纤维改性的影响;通过Box-Behnken中心组合试验设计方法,将酶浓度、酶解温度、酶解时间以及样品pH值因素作为自变量,并以样本SDF得率作为响应值,构建四因素三水平Box-Behnken模型,分析竹笋DF改性工艺。结果表明:经超微粉碎竹笋DF的性质与未改性相比显著更优(P<0.05),粉碎时间0~10 s内,随超微粉碎时间的延长,竹笋SDF得率、持水力与膨胀性升高。经超微粉碎处理10 s后SDF得率(8.60±0.142)%、持水力(5.11±0.050)g·g^(-1)、膨胀性(11.06±0.067)mL·g^(-1)。随超微粉碎的时间进一步延长,竹笋SDF得率、持水力与膨胀性开始下降;在纤维素酶0.1%~0.3%浓度范围内,随着纤维素酶的浓度升高,竹笋SDF得率、持水力及膨胀力均逐渐增大,当纤维素酶的浓度>0.3%,随着纤维素酶的浓度升高,竹笋SDF得率、持水力及膨胀力均逐渐下降;酶解时间60 min,竹笋SDF得率、持水力及膨胀力最佳;当pH达到4.5,竹笋SDF得率、持水力及膨胀力最佳;对竹笋SDF得率影响中最显著因素为纤维素酶浓度(F=28.76),其次为pH(F=18.05)、酶解时间(F=11.43)、酶解温度(F=10.93);Design-Expert回归模型分析显示,酶浓度0.32%、酶解时间85.03 min、酶解温度为50℃,pH值4.81,竹笋SDF得率预测值达到15.89%。

超微电极技术与应用

综述超微电极的特点、分类、制备;超微电极在生物体细胞分析、单分子分析、固体电化学、化学动力学参数测定及痕量物质检测等方面的应用.

甘薯渣纤维素粒度对去势大鼠血脂降低效果的影响

目的:探讨纤维素粒度对其降血脂效果的影响。方法:选用40只雌性SD大鼠随机分组为5组,其中1组大鼠进行伪切除手术作对照,另外4组大鼠做双侧卵巢切除手术,基础饲料喂养恢复1周后,分为空白组、普通纤维素组、超微纤维素组和纳米纤维素组,实验期28 d后解剖,测定血浆和肝脏中脂质指标。体外检测3种粒度纤维素的消化性和吸附性能。结果:3种粒度纤维素对油脂、胆固醇和胆酸钠都有较强吸附,对油脂和胆酸钠的吸附能力随纤维素粒度减少而增加。3种纤维素均降低双侧卵巢切除大鼠血浆总胆固醇、甘油三酯、低密度脂蛋白胆固醇浓度和动脉硬化指数值以及肝脏中总脂肪、甘油三酯的浓度。纤维素粒度与双侧卵巢切除大鼠血浆总胆固醇、甘油三酯、低密度脂蛋白胆固醇浓度呈正相关性。结论:减小纤维素粒度有利于增加纤维素对油脂和胆酸盐的吸附能力,提高纤维素降低双侧卵巢切除大鼠血脂的效果。

甘薯纤维素粒度对高脂大鼠的降血脂作用

为了探讨甘薯纤维素粒度对雄性大鼠的血脂、肝脂的影响。选用40只雄性SD大鼠随机分成5组,其中一组作为空白组,另外4组分别为高脂对照组、普通纤维素组、超微纤维素组和纳米纤维素组。实验喂养28 d后解剖,测定血浆和肝脏中的脂质指标,以及粪便和小肠液中的总胆汁酸含量。结果表明,高脂对照组大鼠体重增加量、采食量、血脂、肝脏脂肪浓度、总胆固醇(TC)、甘油三酯(TG)总含量均显著(p<0.05)高于空白组,说明高脂膳食对大鼠的影响非常明显;普通纤维素组、超微纤维素组和纳米纤维素组的体重增加量、血脂、肝脏中总脂肪、TC、TG总含量均低于高脂对照组,同时,三个纤维素实验组大鼠的排便量以及粪便和小肠液中总胆汁酸含量显著高于高脂对照组,说明三种不同粒度的纤维素均能降低高脂膳食大鼠的血脂、肝脏中总脂肪、TC、TG含量。纤维素粒度与高脂血症大鼠的血清TC、TG、LDL-C浓度呈正相关性。减小纤维素粒度有利于增强纤维素的降血脂、肝脂的作用,纳米纤维素有良好的降血脂作用。

功能性纤维的发展动向

本文介绍了纤维的几种改性方法，着重介绍了各种服用功能性纤维的研究和发展动向。随着高新技术的发展，各个产业领域对纤维材料的需求提出了更多的功能性要求，目前，世界上正应用先进的纤维技术开发特殊功能的超级功能性纤维。

Study on Development Rule of Muscle Fiber in Different Duck Breeds

[Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and Suma duck （ Cherry valley duck ♂ × Jinding duck ♀ ） were fed for 10 weeks to observe the ultrastructure of muscle fiber by electron microscope, and the myofibril diameter and sarcomere length were also determined. [Result] The myofibril diameter increased with ages. Sarcomere length and myofibril diameter did not change significantly with the increasing ages （P〉0.05）. The myofibril diameter of White muscory duck and Jinding duck were thicker, while that of Cherry valley cluck and Suma duck were thinner. Moreover, the sarcomere length of Suma duck and White muscory duck were longer, while that of Cherry valley duck and Jinding duck were shorter. Thus, the basic characteristics of ultrastructure of muscle fiber were consistent in these duck breeds.[Conclusion] The results have an important meaning for duck breeding.

Ultrastructural Study of Secondary Wall Formation in the Stem Fiber of Phyllostachys pubescens

Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well.

Nature,Characteristics and Uitrastructure Observation of Fibers of Seven Kinds of Special Animals

[Objective]Aimed to study the nature,characteristics and ultrastructure of fibers of Ovis aries and several kinds of special animals.[Method]Wool,cashmere,alpaca,Bactrian camel hairs,rabbit hair,mohair and yak hair were used as the experimental materials,and scanning electron microscopy was used to observe their scale structure.[Result]The rake angle of wool was large with an average of 33.2°,the scale density was 16.2-34.9 scales/mm,the average height of scale was 12.95 μm,and the average thickness was 0.63 μm;the rake angle of cashmere was smaller than wool with an average of 20.6°,the scale density was of 10.3-15.6 scales/mm,the scale distance was large,the average height of scale was 16.09 μm,and the average thickness was 0.46 μm;the average rake angle of alpaca was 34.6°,with the average scale height of 5.85 μm,and average thickness of 0.33 μm;the average rake angle of camel hair was 33.5°,with the average scale height of 11.30 μm and average thickness of 0.37 μm;the average rake angle of rabbit hair was 31.2°,with average scale height of 7.03 μm and average thickness of 0.36 μm;the rake angle value of mohair was between wool and cashmere,and the average of which was 23.7°,the scale density value was also between the wool and cashmere,with the average scale height of 15.82 μm and average thickness of 0.61 μm;the average rake angle yak hair was 33.2°,with the average height of 9.08 μm and average thickness of 0.46 μm.[Conclusion]The results of this study could provide a basis for the identification of different fiber types.

凝结水高温回收利用技术深探讨

将工业生产过程产生的蒸汽凝结水及其所附带的低温热,安全的全部回收利用到工业锅炉补给水中。总结目前凝结水回收利用状况及凝结水回收利用中的误区,提出高温凝结水回收利用中的几点要素:用尽汽化潜热、直接降热、降级使用。并进一步论述了凝结水回收处理过程中出现的典型问题;最后总结凝结水处理技术发展历程,详细论述了活性分子膜超微过滤组合多官能团纤维吸附组合工艺的工艺流程及技术特点,运用活性分子膜超微过滤组合多官能团纤维吸附组合工艺,能满足回收利用工业过程蒸汽凝结水的要求,并且节约水资源和能源的效果非常显著。

Ultrastructural changes in hepatocytes after taurinetreatment in CCl_4 induced liver injury

AIM: To search the organelle based changes in hepatocytes after taurine treatment in experimental liver fi brosis induced by CCl_4 administration. METHODS: Thirty rats were divided into two groups. Group 1 (n = 15) was injected with CCl_4 plus taurine and Group 2 (n = 15) with CCl_4 plus saline for 12 wk. At the end of 12th wk, mitochondria, rough and smooth endoplasmic reticulum, and nuclei of hepatocytes were evaluated using a scoring system. The results were compared with histopathological f indings, as well. RESULTS: Taurine treatment reduced fi brosis scores signifi cantly as compared to placebo. Organelle injury scores decreased signifi cantly with taurine treatment. Ultrastructural and histopathological scores in both groups were in strong correlation (r = 0.931 for CCl_4 plus taurine and r = 0.899 for CCl_4 plus saline group). CONCLUSION: Organelle based transmission electron microscopy fi ndings can reflect successfully histological results as well as tissue healing in hepatocytes from hepatotoxin-induced liver fi brosis.

Ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on the stage of liver fibrosis:The first pediatric study

AIM:To investigate the ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on their location in areas of collagen fibroplasia. METHODS:Morphological investigations were conducted on biopsy material obtained from 40 children,aged 3-16 years with chronic hepatitis B. The stage of fibrosis was assessed histologically using the arbitrary semiquantitative numerical scoring system proposed by Ishak et al. The material for ultrastructural investigation was fixed in glutaraldehyde and paraformaldehyde and processed for transmission-electron microscopic analysis. RESULTS:Ultrastructural examination of biopsy specimens obtained from children with chronic hepatitis B showed the presence of two types of oval cells,the hepatic progenitor cells and intermediate hepatic-like cells. These cells were present in the parenchyma and were seen most commonly in areas of intense periportal fibrosis (at least stage 2 according to Ishak et al) and in the vicinity of the limiting plate of the lobule. The activated nonparenchymal hepatic cells,i.e. transformed hepatic stellate cells and Kupffer cells were seen in close proximity to the intermediate hepatic-like cells. CONCLUSION:We found a distinct relationship between the prevalence of oval cells (hepatic progenitor cells and intermediate hepatocyte-like cells) and fibrosis stage in pediatric patients with chronic hepatitis B.

言论

背景：夏至，要做好“蚊虫大战”的准备了!可是你是否一方面担心传统的蚊香、花露水有毒，一方面害怕驱蚊手环、驱蚊贴等新事物不灵，另一方面又怀疑驱蚊草、猪笼草等驱蚊植物噱头大？可选择的灭蚊方式多了，反而更无所适从。

Ultra-small microring resonator based on sub-micrometer fiber

The transfer function of the microring resonator is deduced, and the effects of the normalized loss, coupling coefficient and surrounding media on the resonance performance are investigated thoroughly. Utilizing the improved fused tapering tech- nique and ingenious self-coiling coupling method, a high-quality microring resonator （radius of about 500 I.tm） with larger extinction ratio （〉10 dB） and sharper resonance is designed and fabricated by a segment of continuous sub-micrometer fiber. The microring resonator constructed in this way demonstrates extremely small connection loss with communication fiber in contrast to the planar waveguide technology.