我国木材工业粉尘污染的控制现状与进展(续)

2我国木材工业粉尘污染控制存在的问题及其原因我国已建立了以《中华人民共和国环境保护法》为主体的环境法律体系,也制定和颁布了一系列工业环境保护的法规,并健全了环境保护的监督与管理体制,这对我国的工业环境污染的防止和治理工作起到了积极的作用。     

蛋白质木材胶黏剂(续)

3 蛋白质的特性3.1 蛋白质的分子结构蛋白质的分子是由各种氨基酸以肽键(peptide bond)联接而成的天然复合物,其分子量可大到数十万,形状从线形(fibrous)到球团形(globular)。蛋白质的氨基酸组成,因不同的蛋白质而有差异,以大豆蛋白及鸡羽毛为例,氨基酸的种类及比例列于表3。表3的大豆粉及鸡羽毛粉蛋白质含量分别为48.40%及84.61%;在氨基酸的组成方面,大豆蛋白的天门冬胺酸、谷氨酸及赖氨酸含量较高,而鸡羽毛蛋白的丝氨酸、脯氨酸及含硫的半胱氨酸和甲硫氨酸则含量较高。有些蛋白质除了氨基酸之外,还有其他的官能团,如血     

Floristic diversity and composition of the Biteyu forest in the Gurage mountain chain (Ethiopia): implications for forest conservation

The Afromontane forests of Ethiopia have been under a serious degradation threat. Assessment of floristic diversity and species composition in Biteyu forest of Gurage mountain chain in the central Ethiopia was conducted to examine the pattern of forest structure. Thirty plots of 30 m×30 m were used to record the vegetation and environmental data using systematic sampling technique. The local name, plant scientific names, DBH, height,species abundance and percentage canopy cover of plant species were recorded. Shannon diversity index and Sorensen's coefficients was used for comparison among communities and similar forests in the country. Threats to the forest biodiversity in Biteyu were determined by counting cattle interference and wood stumps as disturbance indicators. Relative Euclidean Distance measures by using Ward's method(linkage) was applied for cluster analysis. Environmental variables were also recorded in each plot. Woody species population structure, basal area and importance value index were analyzed using spreadsheet programs. Data on species distribution and environmental variables in the forest were analyzed by canonical correspondence analysis. A total of 190 species in 154 genera under 73 families were identified. Twenty species were found to be endemic taxa to the Flora Area. Only three plant community types were identified from the cluster analysis due to the high human influence. The Sorensen's coefficient showed the resemblance of the Biteyu forest with other Dry Evergreen Afromontane forests in the country. Moreover, altitude and slope strongly affect the species composition and structure of Biteyu forest. Given the high anthropogenic influence, high endemism, high dependence of the local community on the forest resources, forest conservation and restoration measures should be done by stakeholders.     

Cellular structure and chemical composition of cork from the Chinese cork oak (Quercus variabilis)

Quercus variabilis Blume, the Chinese cork oak, is an oak species with a thick cork outer bark. The cork is exploited at a limited scale in China and considered of lower quality than the commercial cork from Quercus suber. We studied an industrial cork granulate feedstock of Q. variabilis in relation to cellular structure and chemical composition and compared it to Q. suber cork under a material’s perspective. The cork of Q.variabilis has 1.1 % ash, 9.6 % extractives, 34.8 % suberin and 19.1 % lignin. The monosaccharide composition with shows a predominance of hemicelluloses: glucose 42.8 % of total neutral sugars, xylose 27.5 %, arabinose 15.4 %, galactose 9.0 %, mannose 4.0 %, rhamnose 1.2 %. The FT-IR spectrum shows the indicative peaks of suberin. The composition is overall similar to that of Q. suber cork. Q. variabilis cork has the typical cellular characteristics of bark cork tissues with a regular and radially aligned structure of cells without intercellular voids. Solid volume fraction was estimated at approximately 16 %. Compared with Q. suber, the Q. variabilis cork cells are smaller, the cell wall undulation and the overall row alignment less homogeneous, the cell surface is irregular and the solid volume proportion higher. The characteristics of Q. variabilis cork support its use as a cellular material for sealing, insulation and energy absorption, but the overall quality is lower than that of Q. suber cork. The negative impact of the higher density and structural lower uniformity at tissue and cell level should be evaluated for processing and product performance.     

引种银钟花年生长习性观察

对在景洪栽培银钟花抽梢年生长节律、开花习性的观察结果:银钟花的花期主要集中在2～4月,每株开花时间历时不足1个月;花和花序大小株间变异小,但花量株间变异大;3月下旬抽梢,3～4月和6～8月生长较快,5月份生长缓慢,9月以后生长量渐小,到11月停止生长。     

进口材特征与用途(五)

巴西黑黄檀学名 巴两黑黄檀(Dalbergia nigra Fr.All),豆科(Leguminosae)蝶形花亚科(Faboideae),黄檀属(Dal-bergia)商品名及别名 巴西玫瑰木Brazilian Rosewood,杰卡兰达Jacaranda,卡布纳Cabiuna,卡维尤纳caviuna,巴伊亚玫瑰木Bahia rosewood,里奥玫瑰木Rio rosewood树木及分布 大乔木。树高可达38m,靠近基部的树干区径达90～120cm。树木主干干形不规则,老树树干常     

进口材特征与用途(八)

葱叶状铁木豆 学名 葱叶状铁木豆(S.fistuloides Harms),豆科(Leguminosae),苏木亚科(Caesalpinoideae),铁木豆属(Swartzia)     

进口材特征与用途(四)

绿柄桑学名 大叶绿柄桑 Chlorophra excelsa 桑科Moraceae绿柄桑属Chlorophra商品名及别名 埃若科 Iroko,奥杜姆Odoum(加纳,科特迪瓦);塞姆利Semli(塞拉利昂,比里亚);若克科Rokko,奥若科Oroko     

进口材特征与用途(二)

铁力木学名 铁力木(Mesua ferrea Linn)藤黄科(Guttiferae)铁力木属(Mesua L)商用名或别名 三角子、铁棱、铁栗木、咪满那、波斯那克Bosneak(柬埔寨),本拉格Bunnag、嘎吾嘎吾Gau-gau、布拉尔克Boonnark(泰国),米斯阿Mesua(印度),纳嘎塞内Nsgasa Ri(印度尼西亚),瓦瀑Vap(越南),佩纳嘎Penaga(马来西亚)     

进口材特征与用途(六)

鞋木学名鞋木(B.confusa Hoyle),苏木亚科(Caesalpinoideae),鞋木属(Berlinia Soland.ex Hook.f.et Benth.)商品名或别名 姆波萨M’possa(扎伊尔、刚果);特特康尼尼Tetekon-nini;萨曼塔Smanta(加纳);埃科普戈尔Ekpogol(尼日利亚);米里戈巴Melegba,波库里Pocouli(科特迪瓦、喀麦隆);阿比姆Abem,埃萨比姆Essabem(喀麦隆);埃泊阿拉Ebiara(加蓬)。树木及分布 大乔木,树高达12～36m,直径达0.9～1.2m以上,树干常有沟槽和低的板根。分布西非至中非,如加纳、尼日     

进口材特征与用途(一)

应广大读者的要求,结合我国近几年进口木材的情况,2003年我们开辟了“进口材特征与用途讲座”栏目。讲座由北京林业大学工学院博士生导师赵广杰教授负责主讲,北京林业大学在读博士、硕士生曹琳、谢满华、佟永萍、吕宁、黄金田等负责编写。读者如有好的建议和意见请与本刊编辑部联系。     

进口材特征与用途(七)

大花龙脑香 学名 大花龙脑香(D.griffithii Miq.),龙脑香料(Dipterocarpaceae Bl.),龙脑香属(Dipterocarpus Gaertn.f.) 商品名或别名 克隆Keruing,克隆-贝利姆兵Keruing belimbing(马,北婆);阿必通Apitong(菲);古俊Gurjun(印度);卡因斑Kanyinbyan(缅);帕脑Panao,帕脑Panau,巴劳Balau,哈嘎卡克Hagakhak(菲)。 树木及分布 大乔木,树高可达35m,直径1.4m;分布于马来西亚、印度、缅甸、泰国、苏门答腊、婆罗洲、菲律宾。     

进口材特征与用途(三)

铁刀木学名Cassia siamea豆科Leguminosae苏木亚科Caesalpinioideae铁刀木属Cassia商用名及别名 鸡翅木;昂刊Angkanh(柬埔寨);贝阿提Beati(印度);亚哈尔Jahar(马来西亚)树木及分布 树皮厚至中,质硬,易条状剥落;外皮暗     

Early growth and seasonal chemical composition of three indigenous multipurpose tree species (MPTS) in Abeokuta,Nigeria

A study was carried out to evaluate the growth parameters and nutritive qualities of Moringa oleifera, Millettia griffoniana and Pterocarpus santalinoides. The main objective of the study was to assess the potential of the MPTS in supplementing the feed of ruminant animals during the dry season when grasses are scarce and their quality generally fall short of animal requirements. Leaf samples were randomly collected from the trees for estimation of the proximate composition, neutral detergent fibre, acid detergent fibre and gas production using the in vitro technique. Samples were collected three times to represent seasonal variations as follows: November: Early Dry; February: Mid Dry and April: Late Dry seasons. Gas production was recorded at 3, 6, 9, 12, 15, 18, 21, 24, 48, 72 and 96 h of incubation. Mortality rate was less than 5%. M. oleifera recorded the best overall growth respectively followed by P. santalinoides and M. griffoniana. P. santalinoides and M. oleifera retained more leaves in the dry season than M. griffoniana. The dry matter (DM) and ether extract (EE) contents of the MPTS were significantly (P < 0.05) affected by seasons and plant species while there were significant (P < 0.05) species effects on the CP and ADF values. The gas production values and the fermentation parameters indicated the presence of potentially degradable nutrients in the MPTS, which underscores the importance of the tree species as sources of nutrient for ruminant animals during the dry season.     

Economic analysis of industrial agroforestry: poplar (Populus deltoides) in Uttar Pradesh (India)

To meet raw material requirements, Wimco, the biggest manufacturer of matches in India, has been promoting poplar-based agroforestry through an agroforestry project since 1984 approved by the National Bank for Agricultural and Rural Development (NABARD) in the northern region of India. This study aims at evaluating the performance of poplar-based agroforestry in terms of income, employment and environmental impact from the farmers' perspective. Poplar-based agroforestry is economically viable and more profitable than many of the crop rotations followed in the study area. This land-use system is also capable of providing employment opportunities on farms. Sensitivity analyses indicate that this system is not highly risky. However, costs charged by Wimco for technical advice substantially reduce the income from poplar plantation. With agroforestry experience, farmers can expect high dividends in subsequent rotations. Life-time matrices developed through group interviews are useful for thorough economic analyses of agroforestry projects, particularly in cases where data over a period of time are not available.This revised version was published online in November 2005 with corrections to the Cover Date.     

木材工业用胶粘剂的现状及发展趋势(续)

３．３苯酚－甲醛（ＰＦ）树脂 ＰＦ树脂有着良好的耐候性，但存在着成本较高、热压温度高、时间长和对单板含水率要求高等缺点［１２］。在ＰＦ树脂中引入价廉的尿素是降低ＰＦ树脂价格的主要途径。一般来讲，向ＰＦ树脂中引入１０％左右的尿素不会影响树脂的胶合性能和耐老化性，相反可以降低树脂的游离酚和游离甲醛。另外将ＰＦ树脂与ＵＦ树脂共混可以克服ＰＦ的树脂易透胶的缺点。苯酚－尿素－甲醛（ＰＵＦ）树脂的反应机理和结构的研究近年取得了一些进展，在弱碱性条件下，（ｐＨ９．０）反应所得ＰＵＦ树脂中不存在苯酚－亚甲基．尿…     

Anti-hyperglycemic effect of Potentilla discolor decoction on obese-diabetic (Ob-db) mice and its chemical composition

Potentilla discolor is used as an ethnomedicine in treatments of diabetes mellitus in China for years. In the present study, the anti-hyperglycemic effects of a clinical active extract (decoction) from P. discolor were investigated in Ob-db mice. Four week's treatment of P. discolor decoction ameliorated the development of hyperlipidemia, lipid peroxidation and hyperglycemia associated with hyperphagia and polydypsia in Ob-db mice. P. discolor significantly attenuated the increase of blood glucose and cholesterol levels in Ob-db mice. These findings clearly provided evidences regarding the anti-hyperglycemic potentials of P. discolor decoction. High-resolution liquid chromatography-mass spectrometry/mass spectrometry (HR-LC-MS/MS) was used to analyze the phytochemicals in P. discolor decoction. In an comprehensive analysis of phytochemicals in P. discolor, thirty‐five components were identified or characterized in P. discolor decoction and only sixteen of them have been reported in P. discolor previously. There are five major components identified in P. discolor decoction. One of the major components is a flavonoid sulfate, and this is the first evidence for the presences of sulfated flavonoid in P. discolor. Sulfated flavonoids have been reported to improve the complications of diabetes mellitus by inhibition of the aldose reductase in both experimental animals and clinical trials. Therefore, the sulfated flavonoid in P. discolor decoction may in part contribute to the anti-hyperglycemic effect of P. discolor.     

中国木材工业现状与未来(续)

3木地板工业 我国人民生活水平的大幅度改善,有力拉动了对木地板的需求。自1995年来地板业呈现高速发展的势头,无论生产企业数量、生产规模、产值、效益和品牌,木地板在整个木材工业都占较突出地位,已构成了     

木材防护工业的技术进步和面临的问题(续)

2 木材防护工业面临的问题2.1 限制、禁止使用CCA木材防护剂所面临的问题CCA虽然在许多国家遭到限制、禁止使用,但是大多数对此并不是口服心服,许多研究人员正为此向环保部门提出质疑。据最近报导,新西兰木业发出了一份由新西兰和澳大利亚毒理学者编写的报告。该