论胶合板生产中薄板比例及其对经济效益的影响     

钱绳曾 《东北林业大学学报》1989,(2)

文中定量给出了薄板率与厚板率、厚板和薄板及中板的平均厚度、1830mm(6英尺)长木段的所占比例、每立方米1830mm长木段所出的面背板张数的关系等。指出了一个企业生产薄板能力的测算办法。薄板率不是一个科学的技术指标,而应代之以每立方米胶合板平均张数。应尽量加大长木段的比例,生产规格以915mm×1830mm(3′× 6′)为主,如材质允许则以1220mm×2440mm(4′×8′)为主,可以获得最高的薄板比例;应开发厚板市场,生产一定比例的厚板也有利于薄板比例的提高。还论述了薄板率变化对经济效益的影响。  相似文献   

Compatible measurements of volumetric soil water content using a neutron probe and Diviner 2000 after field calibration     

P. J. Burgess    B. R. Reinhard  & P. Pasturel 《Soil Use and Management》2006,22(4):401-404

Field calibrations for a neutron probe and a capacitance sensor (Diviner 2000) for measuring the soil water content of a shrinking–swelling clay soil were substantially different from commonly used default values. Using our field calibrations, the two instruments estimated similar changes in the cumulative water content of a soil profile (0–1 m depth) over one growing season.  相似文献   

Effects of phenylbutazone and indomethacin on the post-operative course following experimental orthopaedic surgery in dogs     

Susan W. Mbugua  Lasse A. Skoglund  Per Lkken 《Acta veterinaria Scandinavica》1989,30(1):27-35

Randomized placebo-controlled crossover studies were carried out in dogs to evaluate how two non-steroidal anti-inflammatory drugs (NSAID) might modulate an acute post-traumatic inflammatory reaction. Two "identical" surgical interventions were performed on the forelimbs of each animal with an interval of 28 days, to enable a paired comparison of the inflammatory signs and the wound/bone healing processes. At one operation 8 dogs received 300 mg phenylbutazone twice daily for 8 days starting on the day before surgery, and at the other operation matching placebo tablets were given. In a similar placebo-controlled trial another group of 8 dogs received 5 mg indomethacin twice daily. With phenylbutazone the post-operative swelling was not significantly reduced compared to placebo, but there was less pain and limping. With indomethacin the swelling was somewhat reduced, but there was no consistent difference to placebo in the pain and limping assessments. None of the drugs appeared to distinctly effect the wound or fracture healing, as evaluated by clinical inspection, comparison of radiographs and comparison of bone sections from the sites of surgery. It proved difficult to select an appropriate dosage of indomethacin due to its high potential to induce GI ulceration and bleeding in dogs. In this experimental surgical model with an acute inflammation, neither phenylbutazone nor indomethacin showed impressive anti-inflammatory or analgesic properties. In the same model paracetamol has proved to significantly and more efficiently, reduce both swelling and pain without any noticeable adverse effects, and appears to be a better alternative than the two presently tested NSAID.  相似文献   

欧洲卫矛嫁接技术     

赵天鹏  丁彦芬  陈舒博 《东北林业大学学报》2016,(7):1-3

以欧洲卫矛为试验材料,研究了接穗粗度、嫁接季节和嫁接方法、嫁接切口绑扎方式不同处理对欧洲卫矛嫁接成活率的影响。结果表明:欧洲卫矛嫁接的最佳接穗粗度为0.55~0.60 cm,成活率可达83.84%;嫁接最佳季节为秋季,最佳嫁接方式为切接,秋季切接是最好的嫁接处理组合,成活率达到87.88%;用塑料薄膜绑扎切口后再用塑料袋罩住嫁接切口的欧洲卫矛嫁接成活率为83.95%,高于其他绑扎方式。  相似文献   

9SJP-20型秸秆揉切挤压机的研制   总被引：1，自引：0，他引：1  

徐英英  王红英  李军国 《农机化研究》2006,(7):86-88

为了解决秸秆中粗纤维难以消化吸收的问题,研制了9SJP-20型秸秆揉切挤压机,在分析其结构、工作原理和计算主要技术参数的基础上,完成了样机的设计工作。样机性能试验表明:该机工作性能稳定,揉切效果良好,并有一定的膨化作用,改善了秸秆的适口性,提高了反刍动物的消化率。  相似文献   

中高浓度螺旋纸浆泵的设计   总被引：1，自引：0，他引：1  

曹卫东  施卫东  潘中永  朱荣生 《农机化研究》2002,(2):63-65

介绍了螺旋离心纸浆泵的使用状况，对单叶片螺旋离心泵的进口结构进行了改进，提供了在这种叶轮上加置短叶片的设计方案，给出了单螺旋叶轮主要几何参数选取的经验公式。  相似文献   

Concentration-Dependent Mobility of Chlorfenvinphos in Isolated Plant Cuticles     

Peter Baur  B. Terence Grayson  Jrg Schnherr 《Pest management science》1996,47(2):171-180

The mobility of chlorfenvinphos in isolated pear (Pyrus communis cv. Bartlett) leaf cuticular membranes (CM) was studied as a function of concentration of chlorfenvinphos sorbed in the cuticle. Mobilities of chlorfenvinphos increased approximately 9-fold when the amount sorbed increased from 1 to 100 μg cm⁻² pear leaf cuticle. From the amounts per area, average volume fractions of chlorfenvinphos in the cuticle were calculated ranging from 2×10⁻³ to 5·1×10⁻². The increase in mobilities was steepest at the lower and levelled off at higher volume fractions. This correlation could be described for the whole range of volume fractions investigated by an equation which assumes homogeneously dispersed chlorfenvinphos. Temperature dependence of mobilities was studied at 17, 25 and 35°C and chlorfenvinphos volume fractions of 5·5×10⁻³ and 0·12, respectively. Arrhenius graphs were linear for both volume fractions, showing that cuticles did not undergo a phase transition due to the high amount of sorbed chlorfenvinphos. However, at a volume fraction of 0·12, the activation energy of diffusion, E_D, was significantly lower (83·6 kJ mol⁻¹) than at 5·5×10⁻³ (135 kJ mol⁻¹). We interpret these findings as evidence for a plasticising effect on cuticular waxes by chlorfenvinphos. So far, such an effect had been demonstrated only for certain adjuvants (ethoxylated alcohols) but not for active ingredients. Chlorfenvinphos not only increased its own mobility in pear leaf cuticles, but also that of 2,4-D in Citrus leaf cuticles. This would be expected if plasticising of waxes was the sole mechanism responsible for increased mobilities. From these data we predict that permeabilities of cuticles to chlorfenvinphos are not constant. Depending on temperature as well as types and amounts of adjuvants, rates of foliar penetration of chlorfenvinphos can be higher if its concentration in the spray liquid is increased.  相似文献   

红莲型CMS水稻线粒体K+ATP通道特性的初步研究     

夏春皎  王卓  徐鑫  马亢  刘学群  王春台 《华中农业大学学报》2006,25(3):219-222

以水稻红莲型细胞质雄性不育(HL-CMS)不育系粤泰A(YTA)和保持系粤泰B(YTB)黄化苗线粒体为材料,研究了YTA和YTB离体线粒体KA TP通道对其诱导调节剂KCl、ATP、ADP和GTP等的响应特性。结果表明,KA TP通道诱导剂KCl,能明显诱导YTA和YTB线粒体膨胀,但YTA的膨胀程度较YTB的明显;KA TP通道的内源性抑制剂ATP对YTA和YTB线粒体膨胀起显著抑制作用;KA TP通道的内源性激动剂ADP和GTP引起的不育系YTA离体线粒体短暂收缩及之后的再膨胀程度均较YTB的明显;此外,比较YTA和YTB离体线粒体在Rh123一起孵育10 min后,KCl和解偶联剂FCCP处理引起的离体线粒体膜电位(Δψm)下降过程,发现前者的线粒体Δψm较后者的易于过早崩解。对水稻HL-CMS不育系YTA和可育的保持系YTB线粒体KA TP通道特性的比较研究表明,水稻HL-CMS不育系YTA线粒体KA TP通道对其诱导调节剂KCl、ATP、ADP和GTP等的响应较YTB的更敏感。  相似文献   

水质对膨润土防水毯防渗效果影响研究   总被引：1，自引：0，他引：1  

周春生  柴建华  史海滨  于健  赵培清 《节水灌溉》2006,(6):27-30

针对我国西北干旱寒冷盐渍化地区渠道防渗存在的问题,对拟引进使用的膨润土防水毯的膨胀性能及防渗效果进行研究,提出推广应用一种新型复合土工合成材料（膨润土防水毯）。选择3种膨润土防水毯产品。采取室内试验,分析了不同浓度及离子溶液对膨润土防水毯防渗效果的影响。试验表明溶液浓度膨润土膨胀性能影响较大．当矿化度大于5g／L时膨胀量明显减小。离子及浓度对韩国1号（两层聚丙烯薄膜防护）防渗性能影响最小,除与膨润土成分及含量有关外,两层聚丙烯薄膜防护层结构对防渗性能也有较大的影响。  相似文献   

中国南部养殖石斑鱼“肿胀病”的研究     

刘荭  江育林 《华中农业大学学报》2002,21(3):273-277

1998年5月至7月间,在中国南部养殖石斑鱼暴发"肿胀病",引起石斑鱼大量发病、死亡.从体表和鳍条的溃疡病灶处分离出2个菌株.形态学观察和生化试验结果表明这2个菌株均为鳗弧菌.将肝、脾、心和肾的上清液接种到CO、FHM、CAB、CK、PG和PC细胞上,没有观察到细胞病变.患病鱼的腹腔中有大量黑色的球状物和腹水,使患病鱼呈现明显的腹部肿胀的症状.组织病理学观察结果表明,这些黑色的球状物由多核细胞组成的增生性组织.  相似文献