新型的林区通讯工具——DZK——A有线／无线通信中央控制台

新型的林区通讯工具——ＤＺＫ－Ａ有线／无线通信中央控制台＠李琳￥江西省鹰潭市工业技术研究所通讯器材，设计，无线电技术，森林防火，应用新型的林区通讯工具——ＤＺＫ—Ａ有线／无线通信中央控制台李琳（江西省鹰潭市工业技术研究所３３５００１）关键词：通讯器材设计无...     

智能电话扩容机

智能电话扩容机ＺＤＫ—１智能电话扩容机采用先进的微电脑、程控交换技术，是一种在原有一条电话外线的情况下进行扩容的智能化仪器，可扩展成４部电话，并留有接口，最终可扩展至１２部，各分机具有一般外线电话全部功能，外线能直拨分机，分机可互相通话，互不干扰。该...     

具有SBZ技术性能的励磁装置

具有ＳＢＺ技术性能的励磁装置该装置是“同步电机失步保护与不减载自动再整步技术”（简称ＳＢＺ技术）项目的组合配套装置。是在ＳＢＺ技术基础上进一步发展和完善的新技术产品，包括ＢＫＬ系列同步电动机半导体励磁装置、ＢＫＬ－Ｇ系列发电机可控硅静止励磁装置和ＷＬ...     

林木生长与养分动态模型研究Ⅰ.杉木直径和高生长方程

在实测和前人研究的基础上，提出了新的杉木直径和高生长方程：Ｚ＝Ｚｍｔ／（Ｋ＋ｔ）．此方程表达形式简单，参数生物意义确切，模拟精确度高，符合和遵循林木生长随树龄（ｔ）变化的基本规律．方程参数Ｚｍ（直径或高生长极值）和Ｋ（林木生长特征系数）与立地指数Ｓ和密度指数ｎ的相关性分析结果反映了杉木生长从属于立地条件、有效空间和时间综合效应的本质关系     

夏威夷澳洲坚果无性萌发与开花的相互关系

夏威夷澳洲坚果无性萌发与开花的相互关系ＮＡＧＡＯ，Ｍ．Ａ．等１９８９——１９９２年，在夏威夷的一个果园进行了澳洲坚果Ｋａｕ（ＨＡＥＳ３４４）、Ｋｅａａｕ（ＨＡＥＳ６６０）和Ｋａｋｅａ（ＨＡＥＳ５０８）开花摸式的研究。开花缺乏同步性延长了收获季节，并增...     

土壤中钾含量的测定方法

土壤中钾含量的测定方法任丽江，康明（河北林学院基础部保定０７１０００）关键词钾素，定量测定，土壤分类号Ｓ１５８．２ＤＥＴＥＲＭＩＮＡＴＯＮＭＥＴＨＯＤＳＦＯＲＳＯＩＬＰＯＴＡＳＳＩＵＭＲｅｎＬｉｊｉａｎｇＫａｎｇＭｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＢａ...     

雷林1号桉叶片营养诊断研究

对雷林１号桉叶营养诊断的采样时间、诊断方法，用临界值法和诊断施肥综合法诊断雷林１号桉施肥“中试的营养状况。结果表明：；雷林１号桉叶片营养诊断的最佳采样时间是８月龄，其Ｎ、Ｐ、Ｋ临界浓度为１７．２、１．３、４．９，ＤＲＩＳ参数为Ｋ／Ｐ、Ｐ／Ｎ和Ｎ／Ｋ。     

辽宁杨,辽河杨,盖杨生长进程研究初报

辽宁杨、辽河杨、盖杨生长进程研究初报刘志成，潘成良，苘胜军，陈鸿雕（辽宁省杨树研究所盖州１１５２００）辽宁杨（Ｐｏｐｕｌｕｓ×ＬｉａｏｎｉｎｇｅｎｓｉｓＺ．ＷａｎｇｅｔＨ．Ｄ．ＣｈｅｎＳｐ．ｎｏｒ），辽河杨（Ｐ．×ＬｉａｏｈｅｎｉｃａＺ．Ｗａｎｇｅｔ...     

检疫性蚜类多媒体鉴定系统通过农业部鉴定

检疫性蚜类多媒体鉴定系统通过农业部鉴定由金瑞华教授等主持的《检疫性蚜类害虫多媒体鉴定系统ＰＱＡＰＭＤＳ—ＥＺ》，于１９９７年５月２日在中国农业大学通过农业部科技司主持的成果鉴定。鉴定委员会一致认为：该成果将昆虫图解式检索表引入微机昆虫分类鉴定系统；将...     

树皮厚度、树皮材积与直径和树高相关关系的研究

树皮厚度、树皮材积与直径和树高相关关系的研究陈东来，秦淑英（河北林学院林学系保定０７１０００）关键词树皮厚度，树皮材积，直径，树高，线性相关中图分类号Ｓ７５８．１ＳＴＵＤＩＥＳＯＮＣＯＲＲＥＬＡＴＩ０ＮＯＦＴＨＩＣＫＮＥＳＳＡＮＤＶＯＬＵＭＥ０ＦＴＲ...     

Forest landscape models: Definitions,characterization, and classification

Previous model classification efforts have led to a broad group of models from site-scale (non-spatial) gap models to continental-scale biogeographical models due to a lack of definition of landscape models. Such classifications become inefficient to compare approaches and techniques that are specifically associated with forest landscape modeling. This paper provides definitions of key terminologies commonly used in forest landscape modeling to classify forest landscape models. It presents a set of qualitative criteria for model classification. These criteria represent model definitions and key model implementation decisions, including the temporal resolution, number of spatial processes simulated, and approaches to simulate site-level succession. Four approaches of simulating site level succession are summarized: (1) no site-level succession (spatial processes as surrogates), (2) successional pathway, (3) vital attribute, and (4) model coupling. Computational load for the first three approaches is calculated using the Big O Notation, a standard method. Classification criteria are organized in a hierarchical order that creates a dichotomous tree with each end node representing a group of models with similar traits. The classified models fall into various groups ranging from theoretical and empirical to strategic and tactical. The paper summarizes the applications of forest landscape models into three categories: (1) spatiotemporal patterns of model objects, (2) sensitivities of model object to input parameters, and (3) scenario analyses. Finally, the paper discusses two dilemmas related to the use of forest landscape models: result validation and circular reasoning.     

气候变化谈判中木质林产品的相关概念及其碳储量核算

森林在维持全球碳平衡中发挥着重要的作用.采伐后木质林产品(harvested wood products,HWP)以下简称木质林产品.木质林产品是森林资源利用的自然延伸.     

Vegetative propagation of Calliandra calothyrsus (Meissner)

The effects of propagation medium and the type of auxin on root and shoot development of stem cuttings of Calliandra calothyrsus were investigated in two experiments. Cuttings were taken from four-week-old coppice shoots from a cleared C. calothyrsus plantation. In Experiment 1, the effects of five propagation media; fine sand (FS) (3 mm), sawdust (SD), fine gravel (FG) (6 mm) and 50:50 mixtures of FS:SD and FG:SD were compared. In Experiment 2, two commercial brands of auxin rooting powder – ‘Seradix 3’ (IBA) and ‘Bouture CF’ (NAA, IBA and MNAA) were evaluated. The experiments were done in a low-cost, non-mist propagator system in Cameroon. Propagation medium had a significant (P = 0.05) effect on mean rooting percentage (FS = 43% and FS:SD = 93%). The effect of the media on shoot growth from the cuttings (height, basal diameter and root biomass) were also significant (P = 0.05). The application of both the commercial brands of auxin significantly enhanced rooting (84% for untreated cuttings and 91% for IBA- treated cuttings). Bouture CF promoted shoot development from the cuttings, while Seradix 3 inhibited shoot development. The results indicate that in the humid lowlands of Cameroon, where seed productivity of C. calothyrsus is known to be very poor, large-scale production of young plants using these techniques is possible. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.     

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.     

表面粗糙度智能测量与处理系统

对目前广泛使用的表面粗糙度检查仪引入一种微机数据采集处理系统，该系统采用12位高速A／D模块，将仪器测量信号及控制信号过接口送入微机，本文给出了设计方案。     

Ruminal Fermentation and Nutrient Digestion in West African Dwarf (WAD) Sheep Fed Leucaena leucocephala Supplemental Diets

Dry season feeding has always posed a problem for ruminant nutrition in sub-Saharan Africa. The availability of browse plants or multi-purpose trees during this period has led to their incorporation in the farming systems. The need therefore to investigate the feeding value and fermentation profiles of WAD sheep fed grass hay with supplemental Leucaena leucocephala formed the objective of this study. Eight 18–24 months old West African Dwarf (WAD) sheep (28.8±4.2 kg body weight) were used in the study. Four of the sheep were fistulated ruminally and rumen pH, ammonia and volatile fatty acid were measured. Dried leaves of L. leucocephala were offered at two levels (25 and 50% of DMI, diets D25% and D50%, respectively) as supplement to a basal hay diet. The basal hay diet without supplement was the control diet. Diet D25% had a higher (p <0.05) ruminal ammonia concentration than the control, while diet D50% had a higher (p <0.05) total volatile fatty acid (VFA) concentration compared to both the control and D25% diets, respectively. Diet D25% had a marginal increase of 6.7% N- retention over the control diet. Organic matter digestibility (OMD) decreased (p <0.05) with level of supplementation. Animals on D50%, D25% and the control diets lost 14, 7.3 and 5%, respectively, of retained energy leading to a negative energy balance. Overall results suggest that a 25% level of supplementation with leucaena gave the best outcome even though a range of 25–50% could be fed during periods of basal diet scarcity.     

二冲程醇类混合燃料发动机点火提前角调节系统的研究

通过分析点火提前角对发动机性能的影响,得出使用醇类混合燃料的二冲程发动机需要改进点火系统的结论。将现阶段汽车工业在点火系统上采用的微机控制点火技术加以改进后移植到二冲程发动机上,在原点火系统中加装点火控制单元ECU并将其改造成电控点火系统。改进后的点火系统可对点火提前角进行标定,对发动机在不同转速和工况下的点火提前角进行实时调节,找到发动机在该转速和工况下的理想点火提前角。改进后的二冲程汽油机可进一步改善发动机的动力性、经济性以及排放性能。     

基于滑移网格的封边机除屑系统仿真优化研究

以封边机除屑系统为研究对象，借助Fluent软件，采用滑移网格技术和离散相模型，对除屑系统内部空气流场和废屑颗粒分布进行三维非定常数值仿真。结果显示，原除屑系统结构进出口压力损失较大，吸附废屑能力较弱；优化后除屑系统结构在刀具转速10 000 r/min、出口风压－1 700 Pa条件下，进出口压力损失减小64.1%，除屑率增加了30%。现场测试显示，优化后除屑系统的除屑效果大幅度提升，仿真结果与现场测试现象，基本保持一致。     

Root distribution ofDactyladenia (Acioa) barteri andSenna (Cassia) siamea in alley cropping on Ultisol. I. Implication for field experimentation

Root observations were carried out on a typic Paleudult in the humid forest zone of south eastern Nigeria in an alley cropping trial usingDactyladenia (Acioa) barteri andSenna (Cassia) siamea as hedgerow trees and the interrow space planted to maize/cassava intercrop. Rooting depth ofD. barteri andS. siamea exceeded 1.6 m. Lateral root propagation ofS. siamea was 15 m, and ofD. barteri was 5 m from the hedgerows. The whole no-tree control plot was within the range of roots of the adjacent hedgerows. Rooting density and depth ofS. siamea in the no-tree control plot was generally higher than of cassava.S. siamea and cassava root density were inversely correlated. Assuming radial symmetry of root propagation, water and nutrients were available from an area 6.1 and 2.3 times larger than the allocated plot size ofS. siamea andD. barteri, respectively. Data obtained in alley cropping trials, not considering lateral root propagation, can be invalidated through exploitation of the no-tree control treatment and nutrient acquisition by hedgerow species from a larger area than allocated, thus underestimating and overestimating the performances of the respective treatments. Possible alternative measures for avoiding root interference are discussed but no good solution can be given.