双孢蘑菇2796菌丝生物学特性研究

研究了双孢菇2796菌丝的生物学特性。结果表明，菌丝生长的最适碳源为麦芽糖，最适氮源为(NH4)2SO4；最适温度为20--25℃；培养基最适含水量为60--65％；最适pH为6—7；菌丝在黑暗条件下生长良好，光照抑制菌丝生长；适宜的CO2浓度可刺激菌丝的生长。     

海南椴生长特性及苗木培育的初步研究

本文论述了海南椴幼年期生长特性，年生长节律，苗期生长规律以及苗木繁育技术。用ｌｏｇｌｓｔｉｃ方程拟合，找出高和直径生长的最优回归方程。     

河北山地森林的特点、地位和发展对策

河北的山地在植被上属于落叶阔叶林地带。河北山地的森林具有立地生产力较低，人工林和天然林年龄小，多与农田、果园和牧地等交叉分布的特点。河北的山地森林在改善山区的生态环境、维持生物多样性、供应城乡居民所需的用材和烧柴及果品、为人民提供游乐活动场所等方面起着重要的作用。河北山地森林应该遵循的发展方针是：要把山区的水土保持和生态环境建设列在首位；要以林为主，协调发展农、果、林、牧的关系；在培养森林上，要采取封山育林和人工造林并重的政策；要把经济林的发展和其他林种结合起来，重视自然保护区森林公园的建设。     

江西三种危害食用菌的绿色霉菌生物学特性研究

本文报道了江西三种危害食用菌的绿色霉菌的生物学特性。它们是:绿色木霉(Trichoderma Viride pers exFn)。产黄青霉(Penicillium Chrysoenum Thom)和构巢曲霉(Aspergillus nidulcms(Eidzm)Winter)。     

有源负载恒温槽性能分析

本文阐述了有源负载恒温槽的工作原理，推导了描述其静态特性的缩减因数表达式，并对这种恒温槽的性能和应用作出了评价。     

继电保护用电流互感器的暂态特性数字仿真及电磁优化设计

本文在分析CT的暂态特性及其动态磁化过程的基础上,建立了计及铁芯饱和、局部磁滞回环、动态剩磁影响的CT单、复励磁暂态过程数字仿真模型,提出了继电保护用P、TPX、TPY、TPz级CT的电磁优化设计方法,编制了计算机程序,用于CT的电磁优化设计及数字仿真分析.     

挖掘机特性测试仪

本文介绍一种新研制出的挖掘机特性测试仪。仪器应用微机技术、自动采集挖掘机特性的电压和电流数据、可在通用示波器上显示或X—y记录仪绘出挖掘机特性曲线。输入标准特性参数后,自动计算并打印出丰满系数,电流和电压测试数据。采样速度为2160点/秒,精度为±1％,量程满足目前使用的4～23m~3电铲.仪器工作可靠,操作维护方便,为挖掘机的调试提供了一个先进的工具。     

CHANGE OF SURFACE CHARACTERISTICS DURINGOXYGEN BLEACHING OF SULPHATE PULP

INTRODUCTIONAtpresent,oxygenbleachinghasbecomeanlndustrializedtechnolOgy.Uptol989,thistechnologyhadbeenusedin58paPerndlls,and50%ofthemwereinEuroPe,20%inNorthemAmencaand20%inJapan.Inrecentyears,severaloxygnbleachiofequiPmenthadbeenintroducedintoChina.Inaword,oxygenbleachinglsasuccessfulandenviron-mentallyaccePtableprocessfOrPulpbleaching.However,littleworkhadbeendevotedtounderstandingthefundamentalaspectsofthissysten1,sotherewaslittledetailedinfOrmationonthel11echanismsofoxygenbleachi…     

The effect of eradication of lice on the occurrence of the grain defect light flecks and spots on cattle hides.

The influence of an eradication programme for lice on the prevalence of light flecks and spots on cattle hides was studied in 33 dairy cattle herds during a period of two and a half years. Lice were eradicated from the main group of herds after 9 to 12 months and the quality of the hides before and after treatment was compared. Hides from slaughtered animals were collected during the study period, tanned and examined with special emphasis on the occurrence of the grain damage light flecks and spots. The prevalence of hides without light flecks and spots increased from 24.2% before treatment to 61.6% after treatment. The prevalence of hides free from the damage increased significantly in all examined anatomical regions. The improvement in hide quality was most marked in the shoulders and neck region which corresponded to the major predilection site of cattle lice. The prevalence of hides with light flecks and spots started to decrease in the first period (2-40 days) after eradication. The changes after treatment suggested that most healing process took place over a period of about 4 months. The eradication programme eliminated the seasonal variation in the prevalence of light flecks and spots which was present before treatment.