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91.
利用在内蒙古东部地区收集的1 570株人工杨树样木资料,通过FORSTAT软件对其二元材积模型进行拟合,比较各个模型的效果,选取最佳模型,以供参考。 相似文献
92.
笔者根据北京林业大学冯仲科教授提出的精准林业的理念,使用全站仪对树木材积进行量测,并将全站仪量测的材积数据与解析法所得砍伐数据进行比较,结果表明,全站仪量测立木材积的精度在91%以上,平均精度在96%左右,完全能满足高精度量测立木材积的要求,建议推广应用。 相似文献
93.
目前现有科技平台的数据库支持已经无法满足未来的科技服务支持,大数据的管理和使用成为了科技平台的发展趋势。如何精准的处理大数据并投入管理显得尤为重要。本文对大数据的概念进行了引入,并分析了大数据时代下大数据的解决方案以及大数据与科技共享服务平台的结合发展。 相似文献
94.
96.
钓鱼岛近海的涡旋及其与马面鲀渔场的关系 总被引:1,自引:0,他引:1
本文根据1981—1984年各年春季(4月),绿鳍马面鲀产卵场的调查资料及产量统计资料,通过水温、盐度、密度σ_t比容偏差10~((?)δ)和地转流等海况要素,对钓鱼岛近海的涡旋特征、强度、位置变化及结合渔况进行分析研究。初步认为钓鱼岛东北海区即黑潮及其分支处附近,存在一气旋型涡旋,涡旋边缘的北侧和西侧流速较小,是马面鲀的过路渔场和产卵场。春季马面鲀的产卵场基本集中在钓鱼岛近海(26°N断面)的涡旋区及其西侧边缘的近底层,水温为17—18℃,盐度为34.6—34.8‰,比容偏差10~((?)δ)为270一290。若以涡旋底部的比容偏差10~((?)δ)作为衡量外洋水强弱的指标,则它与上海、舟山渔业公司4—5月份的马面鲀产量之间的相关系数为0.913;与马面鲀年总产量的相关为0.812。故认为该水文要素可提供渔获量预报的一项指标。马面鲀仔鱼基本沿涡旋周围的海流逐步向东北方向漂移。 相似文献
97.
《Journal of Exotic Pet Medicine》2014,23(2):142-146
The hemodilution effect of manually preheparinized syringes was determined by evaluating the packed cell volume (PCV) and total solids (TS) from blood samples collected from 50 American alligators (Alligator mississippiensis). A volume of 0.2 mL of blood was drawn into 3 syringes of 1 mL: control with no heparin sodium, heparin sodium drawn to 0.1 mL and then expelled, and heparin sodium drawn to 0.2 mL and then expelled. PCV and TS values were determined from each syringe immediately after collection. Mean PCV and TS values were compared between the control and heparin groups using linear mixed modeling. The syringes coated with heparin resulted in a significantly lower mean PCV and TS values when compared with controls, with no significant difference between the heparin groups. This dilution effect was also found to be inconsistent and not accurate from one syringe to another. An adjunct method of obtaining 0.5 mL from already-collected blood samples into 1-mL syringes that were coated with heparin drawn to 0.2 mL and then expelled also showed a significant decrease in PCV and TS values when compared with the control samples, although to a lesser extent. As a result, it cannot be recommended to manually preheparinize syringes when collecting small volume of blood samples from American alligators because significant and unpredictable hemodilution is likely to occur. 相似文献
98.
W.?P.?WaserEmail author A.?Schmitz S.?F.?Perry A.?Wobschall 《Fish physiology and biochemistry》2005,31(1):73-82
The teleost pseudobranch, a reduced mandibular gill arch, morphologically closely resembles a gill hemibranch. It consists
of several filaments bearing numerous lamellae. The vascular system of the pseudobranch also matches that of a gill, with
afferent and efferent filamental arteries and the lamellar blood space. Despite the pseudobranch’s gill-like appearance, however,
a gas exchange function is excluded in many teleosts by overlying opercular epithelium, effectively eliminating diffusional
exchange with the external medium. The physiological function of the pseudobranch is still unknown, though its conspicuously
close association with the ocular choroid rete mirabile, a structure supporting elevated oxygen partial pressures in the eye, suggests a role related to the process of oxygen secretion
into the eyes of teleosts. In this paper we present new stereological data on the pseudobranch of rainbow trout (average weight:
478 ± 114 g, x ± SD, n = 12). The total Cavalieri volume of the pseudobranch was 46.4 μl (97 μl kg−1), consisting of lamellae 49%, connective tissue 43.8%, large blood vessels 4.5%, filamental cartilage 2.3%, and central venous
sinus 1.3%. Lamellae were comprised of pillar and pseudobranchial cells 81%, blood space 12.3%, and lacunar tissue 6.4%. The
inner surface of the blood space in the lamellae was 12.2 cm2 (25.5 cm2 kg−1), and its volume was 2.81 μl (5.88 μl kg−1). The results demonstrate the pseudobranch’s potential for physiological functions requiring a high surface area or surface-to-volume
ratio, i.e. ion transfer, gas exchange and other regulatory processes. More detailed analysis of the function of the pseudobranch,
however, has to remain subject of future morphological and physiological studies. 相似文献
99.
Soumaya Zouari Ellouzi Dorra Driss Sameh Maktouf Monia Blibech Manel Affes Hounaida Kamoun Semia Ellouze Chaabouni Raoudha Ellouze Ghorbel 《Journal of Cereal Science》2014
Gluten extracted from fresh pasta by-products (PG) was enzymatically hydrolyzed by two different commercial proteases (Alcalase 2.4 L and Pancreatin) to different degrees of hydrolysis (DH 2.0, 4.0 and 8.0%). Commercial gluten (CG) was used as reference. The evaluation of functional properties of hydrolyzates from pasta gluten (PGH) and commercial gluten (CGH) showed that Pancreatin hydrolyzates had the highest emulsifying capacities. Regarding the foaming activity, all hydrolyzates performed better than unhydrolyzed gluten. PGH and CGH were added to wheat flour (1%) and their effects on dough rheology were studied. Most hydrolyzates with DH 8% increased dough thermal stability and elasticity during mixing, accelerated the denaturation rate of the protein network, and delayed the gelatinization speed of starch as the temperature increased. Texture profiles and specific volumes of breads from low quality wheat flour with added Pancreatin hydrolyzates (DH 8%) were comparable to those of breads from high quality flour. This showed the potential suitability of PGH and CGH as bread improvers. 相似文献
100.
High ratio cakes made from ozonated flour attained volumes and other quality characteristics comparable to those from chlorinated flours at 36 min ozonation time. Ozone thus appears to be a viable and more environmentally acceptable alternative to chlorine. Extraction of lipids from flour caused deterioration of cake quality which was not restored by ozonation, indicating that lipids were involved in the improving effects of ozonation. Oxidation by ozone led to higher molecular weights of polymeric proteins. 相似文献