麦秸秆/高密度聚乙烯（HDPE）复合材料中纤维分散性的描述模型

麦秸秆纤维作为一种重要生物质资源已被广泛应用于热塑性复合材料中。纤维在复合材料中的分散性是影响复合材料力学性能的重要因素之一,而目前对其定量化的描述和分析方法仍存在一定不足。本研究基于实验获得的纤维尺寸的统计分布规律,利用随机生成算法模拟纤维在复合材料中的分布;构建描述纤维分散性的指标:分散度,单个纤维数和接触纤维数;统计分析纤维含量、纤维大小对分散性指标影响。结果表明单个纤维数随纤维含量增加而增加,但其增量随纤维含量的增加而降低,降低规律符合三次函数。纤维接触数随纤维含量增加,增加规律符合二次函数,亦符合理论估计。纤维大小影响单个纤维数和接触纤维数的增加幅度,但不影响单个纤维数的百分比。分散度随纤维含量的增加呈线性下降规律。纤维分散性的定量化描述为进一步的复合材料性能分析和建模提供了量化指标。     

壳聚糖基复合材料类新型生物医用材料

壳聚糖是由N-乙酰基-D-葡萄糖胺和D-葡萄糖胺单元通过β-D(1→4)连接组成的碱性线性多糖。壳聚糖由于具有良好的生物相容性、生物可降解性和生物活性,已广泛应用于生物医学领域。壳聚糖由于具有许多的活性基团,能进行各种衍生化反应以及与其他材料进行复合制备各类复合材料。本文主要介绍壳聚糖与各类材料如蛋白质、糖胺聚糖、DNA、可降解的聚酯、无机物、合成(离子型和非离子型)的聚合物、或脂质的复合物及其在生物医学上的应用。     

纳米碳聚氨酯复合材料在心血管领域研究应用现状及展望

纳米碳聚氨酯复合材料是一种新型材料,具有特殊的纳米结构和优异的力学、电学和磁学性能,在生物医学领域显示出诱人的潜在应用价值和前景,吸引了越来越多的研究者的关注。本文简要介绍纳米碳聚氨酯复合材料的结构与性能,并对纳米碳聚氨酯复合材料在心血管领域的研究现状以及因其优越的生物学性能在心血管领域的发展趋势进行了综合评述。     

大鲵精子结构研究

为了解大鲵精子超微结构,应用扫描电镜和透射电镜开展了大鲵精子形态结构研究。结果显示:大鲵精子由头部、颈部和尾部3部分组成。精子总长216.36μm±9.93μm(n=30),头部长65.80μm±3.70μm(n=30),颈部较短,多不明显,尾部长153.52μm±3.22μm(n=30)。头部由顶体、穿孔器和细胞核组成;颈部包括核窝、近端中心粒及远端中心粒、线粒体、轴丝和轴纤维;尾部无明显分段,由轴丝、轴纤维、轴丝旁纤维和波动膜组成。大鲵精子内线粒体较少,可能与精子运动缓慢、精子活力维持时间短有关;成熟过程中精子细胞头部包围的胞质分泌物中含有一定数量的线粒体。     

木素过氧化物酶的研究进展

木素过氧化物酶是一种能降解木素,由微生物分泌的胞外酶,广泛应用于生物制浆、纸浆的酶法漂白、有机污染物的降解和环境的生物修复等方面.介绍了木素过氧化物酶的来源、结构与性质、催化机理以及基因工程方面的研究成果,并对其可能带来的工业应用前景以及今后的研究方向进行了展望.     

生物陶瓷多功能人工骨

上海第一人民医院、上海硅酸盐研究所和江苏沙洲县医疗器械厂合作研制成生物陶瓷多功能人工骨。它是由钛合金等复合材料制成,外部喷涂0.3～0.5μm的生物陶瓷展,其上有60～100μm散在微孔,肌肉的附着端还有隧穴,便于固定。新型人工骨经临床应用,证明具有良好的生物相容性,与人体结合牢固,支撑稳     

对萘磺酸钠修饰的石墨烯基纳米银复合抗菌材料的制备及性能评价

制备采用1-萘磺酸钠修饰的石墨烯基纳米银复合材料,并对其性能进行评价。首先制备了石墨烯基纳米银复合材料,采用1-萘磺酸钠修饰,记为AgNP/rGO-NA,然后通过与聚乙烯吡咯烷酮做保护剂的纳米银（PVP/AgNP）的比较,分析其稳定性,抗菌活性,细胞毒性。研究发现,纳米银AgNP在制备的复合材料表面的分布相对均匀,AgNP的质量分数为4.3%,粒径为5~15nm,Zeta电位为-42.5 mV;在无光或光照强度为3000 Lx（勒克斯）的低温光照仪环境下储存10 d,PVP/AgNP聚集作用较为明显,而AgNP/rGO-NA则分散性良好,聚集作用不明显;AgNP/rGO-NA具有更加良好的抗菌活性,生物相容性和相对较低的生物毒性。试验表明经过1-萘磺酸钠修饰的石墨烯基纳米银复合材料质量可靠,性能良好,具有广阔的应用前景。     

热氧老化对麦秸秆/橡胶/PE仿藤条性能的影响

秸塑复合材料(SPC)是一种使用秸秆纤维替代木材纤维的新型木塑复合材料。以麦秸秆和低密度聚乙烯为原料,利用天然橡胶增韧的特性开发出了麦秸秆/橡胶生物质仿藤条。在100℃条件下加速热氧老化60天,观察分析其力学性能和微观结构的变化规律。结果表明,初始条件下,一方面麦秸秆纤维的加入降低了仿藤条的力学性能;另一方面橡胶的加入增强了仿藤条的韧性,起到了弥补作用。老化过程中,材料表面出现裂纹,生物质和PE界面的结合官能团丧失,界面结合能力降低,力学性能下降。结合动力学模型,0~15天为快速降解阶段,材料断裂伸长率降低较快,橡胶的加入降低了老化速率,老化系数降低了70%。含有橡胶的仿藤条在15~60天的老化过程中保持较低的老化速率,起到了抗老化作用。     

2011JEC国际复合材料亚洲展

JEC集团总裁兼首席执行官Frederique Mutel表示：“全球复合材料市场蒸蒸日上，亚洲相关产业的发展还将继续推动这种增长。同时，高级复合材料应用的市场需求也在不断增长，且应用范围非常广泛。我们期待未来5年内，复合材料在电气和电子、汽车、航空等领域的应用会将持续增长。”     

强度干扰后退化森林生态系统中保留木的生态效应研究综述

保留木是指森林生态系统受到强度干扰后所存留的树木,保留木对退化森林生态系统结构与功能的维持和恢复具有多方面的生态效应。在生态系统的尺度上总结了退化森林生态系统中保留木的各种生态效应,主要包括保留木对非生物因子和生物因子(附生生物多样性、动物活动和动物多样性、树木更新、空间结构)的影响。森林生态系统经营中,"绿树保留"的经营方式是基于保留木生态效益的实践应用,它可有效减少采伐对生态系统结构和功能所造成的损失。并将有助于深入理解受到强度干扰后森林生态系统中保留木的多种生态效应,可为退化森林生态系统的恢复与重建提供理论依据。     

川西北高原12个垂穗披碱草居群的核型研究

以川西北高原12个居群的垂穗披碱草为材料,用光学显微镜观察了各居群材料的染色体,对观测所得数据进行了核型分析。结果显示,12个群体中有3个居群的材料具随体;12个居群的核型公式有5种,其中居群203024、205090和Y2097为2n=6x=34m(2SAT) 8sm,居群202068、205106、Y2091、Y2095、Y2120为2n=6x=38m 4sm,居群205116、205218为2n=6x=36m 6sm,居群205097为2n=6x=32m 10sm,居群205096为2n=6x=30m 12sm;核型可分为两类,其中居群205097、Y2095、Y20973属1B型,其它9个居群均为1A型。结果表明,川西北高原不同居群野生垂穗披碱草在核型上发生了变异。     

Shade material evaluation using a cattle response model and meteorological instrumentation

Shade structures are often considered as one method of reducing stress in feedlot cattle. Selection of a suitable shade material can be difficult without data that quantify material effectiveness for stress reduction. A summer study was conducted during 2007 using instrumented shade structures in conjunction with meteorological measurements to estimate relative effectiveness of various shade materials. Shade structures were 3.6 m by 6.0 m by 3.0 m high at the peak and 2.0 m high at the sides. Polyethylene shade cloth was used in three of the comparisons and consisted of effective coverings of 100%, 60% with a silver reflective coating, and 60% black material with no reflective coating. Additionally, one of the structures was fitted with a poly snow fence with an effective shade of about 30%. Each shade structure contained a solar radiation meter and a black globe thermometer to measure radiant energy received under the shade material. Additionally, meteorological data were collected as a non-shaded treatment and included temperature, humidity, wind speed, and solar radiation. Data analyses was conducted using a physiological model based on temperature, humidity, solar radiation and wind speed; a second model using black globe temperatures, relative humidity, and wind speed was used as well. Analyses of the data revealed that time spent in the highest stress category was reduced by all shade materials. Moreover, significant differences (P < 0.05) existed between all shade materials (compared to no-shade) for hourly summaries during peak daylight hours and for ‘full sun’ days.     

Shade material evaluation using a cattle response model and meteorological instrumentation

Shade structures are often considered as one method of reducing stress in feedlot cattle. Selection of a suitable shade material can be difficult without data that quantify material effectiveness for stress reduction. A summer study was conducted during 2007 using instrumented shade structures in conjunction with meteorological measurements to estimate relative effectiveness of various shade materials. Shade structures were 3.6 m by 6.0 m by 3.0 m high at the peak and 2.0 m high at the sides. Polyethylene shade cloth was used in three of the comparisons and consisted of effective coverings of 100%, 60% with a silver reflective coating, and 60% black material with no reflective coating. Additionally, one of the structures was fitted with a poly snow fence with an effective shade of about 30%. Each shade structure contained a solar radiation meter and a black globe thermometer to measure radiant energy received under the shade material. Additionally, meteorological data were collected as a non-shaded treatment and included temperature, humidity, wind speed, and solar radiation. Data analyses was conducted using a physiological model based on temperature, humidity, solar radiation and wind speed; a second model using black globe temperatures, relative humidity, and wind speed was used as well. Analyses of the data revealed that time spent in the highest stress category was reduced by all shade materials. Moreover, significant differences (P < 0.05) existed between all shade materials (compared to no-shade) for hourly summaries during peak daylight hours and for ‘full sun’ days.     

Shade material evaluation using a cattle response model and meteorological instrumentation

Shade structures are often considered as one method of reducing stress in feedlot cattle. Selection of a suitable shade material can be difficult without data that quantify material effectiveness for stress reduction. A summer study was conducted during 2007 using instrumented shade structures in conjunction with meteorological measurements to estimate relative effectiveness of various shade materials. Shade structures were 3.6 m × 6.0 m × 3.0 m high at the peak and 2.0 m high at the sides. Polyethylene shade cloth was used in three of the comparisons and consisted of effective coverings of 100%, 60% with a silver reflective coating, and 60% black material with no reflective coating. Additionally, one of the structures was fitted with a poly snow fence with an effective shade of about 30%. Each shade structure contained a solar radiation meter and a black globe thermometer to measure radiant energy received under the shade material. Additionally, meteorological data were collected as a non-shaded treatment and included temperature, humidity, wind speed, and solar radiation. Data analyses was conducted using a physiological model based on temperature, humidity, solar radiation and wind speed; a second model using black globe temperatures, relative humidity, and wind speed was used as well. Analyses of the data revealed that time spent in the highest stress category was reduced by all shade materials. Moreover, significant differences (P < 0.05) existed between all shade materials (compared to no-shade) for hourly summaries during peak daylight hours and for ‘full sun’ days.     

Effect of conductive polymers coated anode on the performance of microbial fuel cells (MFCs) and its biodiversity analysis

Conductive polymer, one of the most attractive electrode materials, has been applied to coat anode of MFC to improve its performance recently. In this paper, two conductive polymer materials, polyaniline (PANI) and poly(aniline-co-o-aminophenol) (PAOA) were used to modify carbon felt anode and physical and chemical properties of the modified anodes were studied. The power output and biodiversity of modified anodes, along with unmodified carbon anode were compared in two-chamber MFCs. Results showed that the maximum power density of PANI and PAOA MFC could reach 27.4 mW/m(2) and 23.8 mW/m(2), comparing with unmodified MFC, increased by 35% and 18% separately. Low temperature caused greatly decrease of the maximum voltage by 70% and reduced the sorts of bacteria on anodes in the three MFCs. Anode biofilm analysis showed different bacteria enrichment: a larger mount of bacteria and higher biodiversity were found on the two modified anodes than on the unmodified one. For PANI anode, the two predominant bacteria were phylogenetically closely related to Hippea maritima and an uncultured clone MEC_Bicarb_Ac-008; for PAOA, Clostridiales showed more enrichment. Compare PAOA with PANI, the former introduced phenolic hydroxyl group by copolymerization o-aminophenol with aniline, which led to a different microbial community and the mechanism of group effect was proposed.     

萆薢类药材的HPLC指纹图谱研究

应用HPLC方法测定了薯蓣属根状茎组10种1亚种1变种植物23个样本,建立了萆薢类药材总皂苷元粗提物的HPLC指纹图谱.色谱柱为Zorbax Eclipse XDB-C_(18)柱(4.6×250 mm,5 μm),流动相为乙腈-水,柱温30℃,检测波长为203 nm.结果表明,用上述条件所建立的指纹图谱共标示出7个共有峰,且可较全面地反映萆薢类药材的皂苷元类成分,为萆薢类药材薯蓣属根状茎组植物鉴别及质量控制提供一种方法.     

Karyotype Analysis of 5 Species of Polygonatum Mill.

The present paper reports the chromosome numbers and karyotypes of five species in Polygonatum from Anhui of China. The materials used in this work are listed in Table 1, Photomicrographs of somatic metaphase and karyograms of the five species of Polygonatum in Plate 1, 2, 3, the idiograms in Fig. 1-11 and a comparison of the karyotype of them is provided in Table 2. The results are shown as follows: 1. Polygonatum odoratum (Mill.)Druce Two materials were examined. One from Mt. Huangshan, Anhui, has 2n= 16 = 10m (3sc)+ 6sm (Plate 1 :A, B). The idiogram is shown in Fig. 1. The chromosomes range in length from 2.85 to 8.85 μm, with the total length 48.63μm and the ratio of the longest to the shortest 3.11, The karyotype belong to Stebbins’(1971) 2B. The two chromosomes of the first pair have arm ratios 1.01 and 1.29 respectively, and The first pair has one chromosome carrying a satellite attached to the short arm, showing heterozyosity .The chromosome num ber of 2n= 16 in P. odoratum and its karyotype are reported for the first time. The other from Langyashan, Chu - xian, Anhui, is found to have 2n = 18 = 10m (Isc)+2sm+6st(2sc) (Plate 1: C, D). The idiogram is shown in Fig. 2. The chromosomes range in length from 2.43 to 8.29μm, with the total length 46.67µm and the ratio of the longest to the shortest 3.41. The karyotype is also of 2B. In a somatic chromosome complement the 2nd pair have one chromosome carrying a satellite attached to the long arm, showing heterozygosity. 2. Polygonatum filipes Merr. Two materials were examined. One from the Huangshan, Anhui is found to have two cytotypes: 2n= 16 and 2n=22. This paper reports one of them. The karyotype formula is 2n=22=8m+8sm(2sc)+6st(Plate 3: Q, R). The idiogram is shown in Fig. 3. The chromosomes range in length from 2.55- 5.85μm, with the total length 45.01 μm and the ratio of the longest to the shortest 2.29. The karyotype belongs to 3B. The other material from the Fangchang, Anhui, is shown to have four cytitypes: 2n= 14, 2n= 16, 2n=20 (Plate 3: W) and 2n=22. This paper reports two of them. Type I: the karytype formula is 2n=14=10m+4sm (Plate 3: S, T). The idiogram is shown in Fig. 5. The chromosomes range in length from 2.59 to 7.61μm, the total length 37.44μm and the ratio of the longest to the shortest is 2.94. the karyotype belongs to 2B. Type II :The karyotype formula is 2n=16=8m+4sm+4st (Plate 3: U, V). The idiogram is shown in Fig. 4. The chromosomes range in length from 2.65 to 8.21 μm, the total length 46.01 μm and the ratio of the longest to the shortest 3.10. The karyotype belongs to 2B. The chromosome numbers of 2n=20, 2n= 14 and 2n=22, and karyotype of 2n= 14 and 2n=22 in P. filipes are reported for the first time. 3. Polygonatum cytonema Hua Two materials were examined. One from the Langyashan, Chuxian, anhui, is found to have 2n = 18 = 8m (2sc)+ 6sm+ 4st (Plate 2: K, L). The idiogram is shown in Fig. 7. The chromosomes range in length from 3.41 to 9.21 μm, the total length 56.34μm and the ratio of the longest to the shortest is 2.70. The karyotype belongs to 2B. The other material from the Huangshan, Anhui, has two cytotypes: 2n=20 and 2n= 22. Type I: The karyotype formula is 2n= 20= 8m+ 6sm+ 6st (Plate 2: M, N). The idiogram is shown in Fig. 8. The chromosomes range in length from 1.75 to 5.03μm, with the total length 32. 91μm and the ratio of the longest to the shortest 2. 87. The karyotype is also of 2B. Type II: The karyotype formula is 2n=22=6m+ 8sm+4st+ 4t (Plate 2: O, P ). The idiogram is Shown in Fig. 10. The chromosomes range in length from 1.75 to 4.95 μm, with total length 35.05μm and the ratio of the longest to the shortest 2.83. The karyotype brlongs to 3B. 4. Polygonatum desoulayi kom. The material from Xuancheng, Anhui, is found to have karyotype 2n = 22 = 10m (2sc) + 6sm (lsc) + 6st ( Plate 2. I, J). The idiogram is shown in Fig. 6. The chromosomes range in length from 1.86 to 5.61μm, with the total length 41.98μm and the ratio of the longest to the shortest 3.02. The karyotype is also of 3B. The first pair has one chromosome carrying a satellite attached to the long arm, showing heterozygosity. The chromosome number and karyotype of Chinese material are reported for the first time. 5. Polygonatum verticillatum (L.) All. The material from the Langyashan, Chuxian, Anhui is found to have two cytotypes. Type 1: the karyotype formula is 2n = 18 = 2m+ 2sm+ 10st+ 2t+ 2T (Plate 1: G, H). The idiogram is shown in Fig.9. The chromosomes range in length from 1.86 to 4.03μm, with total length 28.28μm and the ratio of the longest to the shortest 2.17. The karyotype classification belongs to 3B. Type II: The karyotype formula is 2n=24=6m+4sm+12st+2T (Plate 1: E, F). The idiogram is shown in Fig. II. The chromosomes range in length from 2.01 to 5.03μm, with total length 41.36μm and the ratio of longest to shortest 2.50. The karyotype is also of 3B. The chromosome numbers and karyotypes of Chinese material are reported for the first time.     

Sugarcane bagasse as alternative packing material for biofiltration of benzene polluted gaseous streams: a preliminary study

Removal of benzene vapor from gaseous streams was studied in two identically sized lab-scale biofiltration columns: one filled with a mixture of raw sugarcane bagasse and glass beads, and the other one packed with a mixture of ground sugarcane bagasse and glass beads, in the same volume ratio, as filter materials. Separate series of continuous tests were performed, in parallel, under the same operating conditions (inlet benzene concentration of 10.0, 20.0 or 50.0 mg m(-3), and superficial gas velocity of 30.6, 61.2 or 122.4 m h(-1)) in order to evaluate and compare the influence of the packing material characteristics upon the biofilter effectiveness. The maximum elimination capacities obtained, at an inlet load of 6.12 g m(-3) h(-1), were 3.50 and 3.80 g m(-3)packibng material h(-1) with raw and ground sugarcane bagasse, respectively. This was a preliminary study and the results obtained suggest only a limited application with more work needed.     

反萼银莲花的核型分析

本文报道反萼银莲花的染色体数目及核型。其核型公式为K(2n)=6m+4sm(1SAT)+4st(1SAT)+2t,按照Stebbins的核型对称性分类标准应属于“2A”型。同时对本属的进化等问题也作了初步讨论。     

THE EFFECT OF WATER HARDNESS AND TEMPERATURE ON WATER STERILIZATION BY MIXTURES OF DETERGENTS AND QUATERNARY AMMONIUM COMPOUNDS

SUMMARY: Six QAC detergent mixtures and the QACs alone were tested for bactericidal efficiency in hard and distilled water, using E. coli as test organism, contact times of 1, 2 and 5 min and temperatures of 5, 10 and 17°.
The efficiencies of the unformulated QACs were dissimilar. With all, 200 p/m in hard water was less efficient than 50 p/m in distilled water. The efficiencies of the QAC detergent mixtures were not related to that of the pure QAC, the efficiency of a QAC being increased by one detergent formulation and decreased by another. All materials were least efficient at 5°.