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1.
笔者分析了贵州省食用菌产业特点与产业优势,认为贵州食用菌产业在自然条件、交通条件以及政策条件等方面均具有较大优势;全省食用菌规模逐渐扩大,品牌效应凸显。进一步总结了贵州省食用菌产业存在的问题,即缺乏行业规范,产品结构较为单一,行业人才匮乏。继而提出了贵州省食用菌产业可持续性发展建议,即加大食用菌产业的开发程度,加强科技支撑及专业人才培养,政府统筹,建立行业标准,重视菌渣的综合开发利用,以实现本省食用菌产业的后发赶超和可持续性发展。  相似文献   
2.
本文应用大挠度理论分析了初始缺陷对板件超屈曲强度的影响,并为板件后屈曲分析提出了一个样条函数半分析计算法.该法对各种载荷及位移边界条件板件均可进行计算,与有限元法等相比较,具有计算量少,精度高等显著特点.数值计算结果为冷弯型钢结构设计提供了较完善的理论依据.  相似文献   
3.
人工接种试验结果表明,雪腐格氏霉(Gerlachia nivalis)引起的小麦成株期叶枯、鞘枯和穗腐,鞘枯使小麦穗粒重减少2.1%~27.1%,千粒重降低9.5%~16.9%;穗腐使小麦穗粒重减少9.6~33.9%,千粒重降低7.8%~17.9%;鞘枯—穗腐复合症状使穗粒重减少10.2%~55.2%,千粒重下降9.5%~14.8%;叶斑—鞘枯—穗腐使穗粒重减少11.7%~47.1%,千粒重下降12.1%~18.3%。  相似文献   
4.
甲醛捕捉剂在胶合板生产中的应用   总被引:7,自引:0,他引:7  
普通UF树脂胶中添加甲醛捕捉剂H300或H800后,其固化时间明显延长.采用H300或H800改性的UF醛树脂胶黏剂生产胶合板,在保证胶合强度的前提下,板材的甲醛释放量达到国标E2或E1级要求.  相似文献   
5.
杉木林地套种绿肥筛选初报   总被引:4,自引:1,他引:3  
收集了三十种绿肥,在杉木当年造林地上进行套种试验,根据其生长状况、生物量、覆盖度及对杉木生长的影响,把供试绿肥分成三类,初步筛选出羽扁豆、决明豆、日木草为适宜杉木林地种植的林用绿肥。同时对今后林用绿肥的选择提出了有益的建议。  相似文献   
6.
A field experiment was conducted during the winter season of 1992–93 and 1993–94 at Agricultural Experimental Farm, Giridih, Bihar to evaluate the intercropping systems of legumes, gram ( Cicer arietinum L.), pea ( Pisum sativum ) and lentil ( Lens culinaris ) with wheat ( Triticum aestivum ) in 1:1 and 2:1 'row replacement series'. Intercropping systems were assessed on the basis of new indices termed as actual yield loss (AYL) and intercropping advantage (IA). This paper highlights the comparative effectiveness of evaluating the intercropping systems through the existing intercropping indices like LER, RCC, aggressivity. The indices AYL and IA seem to be more appropriate particularly when per plant yield is considered. Intercropping reduced the yield of component crops compared with respective pure stands. Wheat + pea in 1:1 row replacement series gave the highest wheat yield equivalent value (3.02 t ha−1) followed by wheat + lentil (2.91 tha−1). When the actual sown proportion was considered wheat + lentil (1:1) resulted in maximum AYL (+0.610) and IA (+0.279) values. This treatment also gave the maximum monetary advantage (Rs 5985.45 ha−1).  相似文献   
7.
改善E1级胶合板用UF胶粘剂预压性能的研究   总被引:1,自引:0,他引:1  
利用氧化淀粉在树脂合成后期、API在调胶时加入分别对脲醛树脂进行改性,探讨改性UF对胶合板预压强度的影响。采用正交实验法对比改性后胶合板的预压性能和改性后胶合板的甲醛释放量的变化。结果表明:随着API量的加大,胶合板的预压性能得以提高;而氧化淀粉改性后则随着量的加大,一定范围内胶合板的预压性能得以提高,加入量继续加大后反而下降。  相似文献   
8.
Abstract. Soil samples from a 32-year grassland field experiment were taken from 0–5, 5–10, and 10–15 cm soil depths in February 2002. Plots received annual treatments of unamended control, mineral fertilizer, three rates of pig slurry and three rates of cow slurry, each with six replicates. Samples were analysed for cation exchange capacity (CEC), exchangeable cations (Na+, K+, Ca2+, Mg2+), pH and Olsen P. Exchangeable sodium percentage (ESP) was calculated as a sodicity indicator. Mean ESP was generally greater for slurry treatments than the control, with a trend of increasing ESP with application rate. This was particularly marked for cow slurry. At 0–5 cm depth ESP increased from 1.18 in the control to 1.75 at the highest rate of pig slurry and 5.60 at the highest rate of cow slurry. Similar trends were shown for CEC, exchangeable Na+, K+ and Mg2+, Ca2+ and Olsen P. The build-up of soil P due to slurry applications, together with this combination of physical and chemical factors, may increase the risk of P loss to surface waters, particularly from soils receiving high rates of cow slurry.  相似文献   
9.
ABSTRACT: Chub mackerel (34–35 cm, approximately 500 g), which were caught by fishing with a rod and line at the Bungo Channel, Oita prefecture, were rested overnight in a fish preserve and either killed by decapitation (control group) or allowed to struggle in air for 30 min (struggled group). Muscle samples were excised every 4 h, and measurements on breaking strength and histological observations were done for both groups. The breaking strength of muscle in the control group was significantly higher than that in the struggled group, whereby a decrease in breaking strength was delayed for 12 h compared to the struggled group. Light microscopy showed space extension among muscle cells in association with a decrease in breaking strength. Especially in the struggled group, the extended area was larger and the difference in area was significant at the time when breaking strength showed a significant difference. Using electron microscopy, the extended area showed cut and/or disappeared collagen fibrils. From these results, it was demonstrated that struggling to death promoted the degradation of collagen fibrils and the weakening of connective tissue and, resultantly, led to the faster softening of muscle of chub mackerel.  相似文献   
10.
Kyounghoon  LEE  Tohru  MUKAI  Donhyug  KANG  Kohji  IIDA 《Fisheries Science》2004,70(6):1051-1060
ABSTRACT:   An application of the acoustic Doppler current profiler (ADCP, 153.6 kHz) in combination with a scientific echo sounder (EK60, 38 and 200 kHz) was investigated to estimate the density of krill Euphausia pacifica . The acoustic backscattering strength from sound scattering layers was compared with biomass estimates from midwater trawls. Euphausia pacifica was targeted among mixed species populations in the sound scattering layer in the offshore Funka Bay area of Hokkaido, Japan. The frequency characteristics of acoustic backscattering by krill were calculated using a distorted wave Born approximation scattering model at three frequencies. Krill aggregations identified from the EK60 data were extracted as the mean volume backscattering strength difference between two frequencies. They were then used to identify similar aggregations in the ADCP data by matching observation times and depths for the two methods, which were applied simultaneously. Results from the comparison of the mean volume backscattering strength and the density calculated from the ADCP and EK60 showed that ADCP can be used to measure density and spatial–temporal distribution of krill aggregations. Current speed and direction at the study site were found to be 16.1 cm/s and 187.0°, respectively, and krill speed and direction (including the current component) were found to be 19.8 cm/s and 172.2°, respectively. Based on the ADCP data, the net speed and direction of the krill aggregations were found to be 5.9 cm/s and 128.0°, respectively.  相似文献   
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