木材表面化学镀处理技术

现实生活中电子产品在室内环境中的运用日益增多,为解决木质产品的电磁屏蔽性,将电子产业成熟的化学沉积金属镀工艺技术引入到木材处理中,阐述了化学镀的机理及其在木材加工中的利用,以木材化学镀铜、镀金工艺为例,从其研究进展、处理工艺、质量评价等方面分析了木材化学镀铜、镀金处理后材料的性能以及生产应用的可行性.     

榉木贴面装饰板表面化学处理

研究采用H2O2为主剂的木材表面处理剂对榉木贴面板进行刷涂处理,结果表明：（1）处理的贴面板表面自然、美丽,材色一致;（2）处理的贴面权力学性能无影响2（3）油漆安全性试验符合要求;（4）外观装饰质量与进口装饰板一致。     

广州地区“青山绿地”工程生态效益

研究了广州地区城市绿地系统森林植物-土壤系统生物同化、吸储、固定C,P,K,SO₂,Pb,Cd的生态效益,结果表明:研究区域内绿地系统土壤中有机C储量最高达184t/hm2,最低为24.6t/hm2;TN储量最高达16.7t/hm2,最低为2.0t/hm2;Pb,Cd储量最高分别达837.4kg/hm2、3.9kg/hm2,最低分别为577kg/hm2、1.2kg/hm2;植物叶对SO₂的积累量以高山榕最高,海芒果最低;小叶榕叶吸收固定Pb量最高为22.6g/hm2,尾叶桉叶和白玉兰叶吸收固定Cd量最高达0.15g/hm2。       

甜高粱秆酿酒前后化学组分纤维特性及制浆性能的研究

对甜高粱秆及其酿酒后残渣的纤维形态、化学组分进行观察和测定发现,甜高粱秆的发酵酿酒过程并没有对其纤维造成严重损伤,二者均具有较大的纤维平均长度和长宽比,且纤维形态良好.在化学组分上,甜高粱秆及其酿酒后残渣的综纤维素和α-纤维素含量较高,木素含量少,均是较好的造纸原料.制浆性能研究表明,甜高粱秆酿酒后残渣易蒸煮,用碱量低,得率高,成纸具有较好的物理强度,将甜高粱秆酿酒后残渣用于制浆造纸是合理利用酿酒残渣的有效途径.     

Changes in the physical and chemical properties of six Japanese softwoods caused by lengthy smoke-heating treatment

The effects of prolonged smoke-heating treatments on wood quality were investigated. Six Japanese softwoods were smoke-heated for 100 and 200h at a temperature of 75° ± 5°C, which was recorded inside the log. After smoke heating, wood quality, including moisture content, amounts of chemical components, relative degree of crystallinity (RDC) of cellulose, and sapwood color were examined. Moisture content decreased as a result of smoke heating, especially in sapwood, leading to a uniform distribution of moisture content within a log. Almost no difference was found in the amounts of chemical components between the control woods and the woods that were smoke-heated for 100h. However, in the wood that was smoke-heated for 200h, the amounts of holocellulose decreased, suggesting that thermal deterioration and/or degradation of hemicelluloses had occurred. We assume that the increase in RDC was caused by smoke heating with the crystallization of cellulose and/or thermal degradation of hemicelluloses. Almost no differences were found in sapwood color between the control woods and the woods that were smoke-heated for 100h. In the wood that was smoke-heated for 200h, however, L*decreased, whereas a* and b* increased. As a result, E*ab, showing the total color change, increased, resulting in a deeper color. These results suggest that thermal degradation of hemicelluloses was caused by smoke heating for over 100h. Therefore, smoke heating of softwood logs using a commercial-scale kiln should not exceed 100h.     

基于聚类分析的土壤理化性质分布研究

基于东莞林科园土壤物理性状的相似性,运用组平均法聚类(UPGMA),将20个土壤剖面划分为4类,并探讨不同物理性状的土壤类型的化学性质的分布规律.研究结果表明,土壤容重与自然含水量之间具有高度负相关(R=-0.98),土壤物理性状指标的大小随着土壤容重的增大而减小.土壤物理性状指标较大的土壤酸性较强,但不同土壤类型下的pH之间没有显著差异(P＞0.05).不同土壤类型下的有机质之间没有显著性差异(P=0.82145),与土壤pH之间只有较弱的正相关(R=0.26),与土壤阳离子交换量之间具有高度的正相关(R=0.97).不同土壤类型下的全氮、速效磷、速效钾含量均没有显著性差异(P＞0.05),碱解氮含量具有极显著差异(P=0.00084),物理性状较差的土壤类型的速效养分含量较高.     

几种除草剂对金钟藤的杀灭效果初析

采用喷雾法研究9种药剂对金钟藤生长状况的影响,通过分析几种药剂对金钟藤绿枝条和老茎鲜重的抑制率,得出以下结果:对金钟藤绿枝条和老茎活性最高的均为2,4-滴丁酯,其抑制率分别为98.90%和81.06%,;其次为莠去津,抑制率分别为为95.07%和66.59%。     

竹叶主要化学成分分析及其生物活性研究现状

就竹叶中黄酮类、活性多糖、氨基酸等主要化学成分及其生物活性研究现状进行了综述。     

落叶果树主要病害的化学防治技术及展望

论述了落叶果树主要病害的种类、病害化学防治的现状、病害化学防治中出现的问题,并对今后果树病害化学防治进行了展望,以保证果树的高效、高产和优质生产。     

Important insect pests of poplars in agroforestry and strategies for their management in northwestern India

Today, more than 143 species of insects infest both indigenous as well as exotic species of poplars in northwestern India, with about 65 species infesting Populus deltoides alone. Random sampling surveys (1984-2002) were undertaken in lower hills and plains of six states (Uttar Pradesh, Uttaranchal, Haryana, Punjab, Himachal Pradesh, and Jammu and Kashmir) in this region. The survey included 36 nurseries, 84 large ( ≥ 3 ha) and 255 small (< 3 ha) block and bund plantations and recorded seven species causing outbreaks. However, eight insects having wide spread distribution in this region were identified as posing a threat to agroforestry with P. deltoides and need to be managed. Amongst these, three species (Clostera cupreata, C. fulgurita and Apriona cinerea) were ranked as 'major pests' as they had relatively higher incidence (> 50% of attack) and caused extensive economic loss during outbreaks, coupled with tree mortality which persisted for several years in succession over large areas. Five insects were identified as 'potential pests', as they also caused heavy infestation and economic loss, but only in some years, on a localized scale and with no large scale plant mortality, but need to be checked to improve productivity. The 'potential pests' were: one species in plantations (Ascotis selenaria) and four insects in nurseries [(Eucosma glaciata , Phalantha phalantha, Nodostoma waterhousie and white grubs) with >50% incidence]. Integrated pest management practices, comprising cultural methods, use of bio-pesticides, tolerant poplar varieties/clones, natural enemies, recommended safe insecticides and avoiding alternate host plants of the pest, are discussed for important pests.