森林工程装备底盘研究综述   总被引：2，自引：0，他引：2  

朱阅  阚江明  徐道春  刘晋浩 《森林工程》2015,(2):97-102

随着我国林业的发展和劳动力日益紧张,森林工程作业机械化的重要性更加凸显。在我国山地、丘陵地区,森林工程装备底盘的性能决定了森林工程装备能否"上山入林",影响森林工程机械化的进程。本文对近些年国内外装备底盘上的研究成果进行介绍,包括具有较强越野能力的装备底盘以及有助于改善底盘性能的关键机构(悬架、转向、车轮),分析各自的优缺点,基于我国典型林区立地条件的基础上提出适合我国山地、丘陵地区作业的森林工程装备底盘的性能要求。  相似文献   

Does actor power impede outcomes in participatory agroforestry approach? Evidence from Sal forests area,Bangladesh     

K. K. Islam  S. Jose  Masakazu Tani  Kimihiko Hyakumura  Max Krott  Noriko Sato 《Agroforestry Systems》2015,89(5):885-899

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杨树不同无性系根系生长的比较     

吴丽云  令狐荣钢  阚荣飞  王媛媛  江秀莲  陆发利 《防护林科技》2015,(7)

通过对20个杨树无性系的根系生长进行的比较及聚类分析研究,结果表明：20个杨树无性系不定根总长度和数量均具有较大的差异,其中,中驻1号不定根总长度最长,达到35.6 m,其次是 NL351、T26和中驻6号,最小的为109,仅为15.4 m。数量最大的也是中驻1号,共65根;中驻6号、W07和 I107次之;最小的为 W03和109,均为24根。基部直径在2 cm 以下的不定根占不定根总数量的60%~80%;聚类分析将20个杨树无性系分成6类。  相似文献   

Responses to the Standard for Exchange of Nonclinical Data (SEND) in non-US countries     

Takayuki Anzai  Masamichi Kaminishi  Keizo Sato  Laura Kaufman  Hijiri Iwata  Dai Nakae 《Journal of toxicologic pathology》2015,28(2):57-64

The Standard for the Exchange of Nonclinical Data (SEND), adopted by the US FDA, is part of a set of regulations and guidances requiring the submission of standardized electronic study data for nonclinical and clinical data submissions. SEND is the nonclinical implementation of SDTM (Study Data Tabulation Model), the standard electronic format for clinical regulatory submissions to FDA. SEND, SDTM, and the associated Controlled Terminology have been developed by CDISC (Clinical Data Interchange Standards Consortium). In order to successfully implement SEND, interdisciplinary contributions between sponsors and CROs, need a model for task allocation. This is being undertaken by the Pharmaceutical Users Software Exchange (PhUSE). Because SEND is currently the preferred submission format of the US FDA only and will become required by it starting in December 2016, only American academic societies and companies are actively involved. An exception to this is the INHAND initiative, which leads the way in standardizing terminology for toxicological pathology. On the other hand, international globalization of other clinical and nonclinical practices is not feasible because there are substantial differences between the US and non-US countries in CRO involvement in drug development. Thus, non-US countries must consider and develop approaches to SEND that meet their needs. This paper summarizes the activities of the major organizations involved in SEND development and implementation, discusses the effective use of SEND, and details a compliance scheme (research material of the Showa University School of Medicine) illustrating how pharmaceutical companies can complete a large amount of work up to an FDA application with the effective utilization of CROs and solution providers.  相似文献   

Preparation, characterization, and antioxidative effects of oligomeric proanthocyanidin-L-cysteine complexes     

Fujii H  Nakagawa T  Nishioka H  Sato E  Hirose A  Ueno Y  Sun B  Yokozawa T  Nonaka G 《Journal of agricultural and food chemistry》2007,55(4):1525-1531

Controlled acid-catalyzed degradation of proanthocyanidin polymers in grape seeds together with L-cysteine led to oligomeric proanthocyanidin-L-cysteine complexes along with monomeric flavan-3-ol derivatives being isolated, and their structures were confirmed on the basis of spectroscopic data and by chemical means. In addition, comparative studies on the antioxidative and survival effects of oligomeric proanthocyanidin-L-cysteine complexes and proanthocyanidin polymers were performed. The oligomeric proanthocyanidin-L-cysteine complexes showed higher bioavailability and antioxidant capacity and enhanced survival time in the animal test groups. In addition, it is suggested that the oligomeric complexes may help to prevent oxidative stress and may reduce free radical production.  相似文献   

Papaya seed represents a rich source of biologically active isothiocyanate   总被引：1，自引：0，他引：1  

Nakamura Y  Yoshimoto M  Murata Y  Shimoishi Y  Asai Y  Park EY  Sato K  Nakamura Y 《Journal of agricultural and food chemistry》2007,55(11):4407-4413

In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate.  相似文献   

Enantioseparation of isoxanthohumol in beer by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography     

Kodama S  Yamamoto A  Sato A  Suzuki K  Yamashita T  Kemmei T  Taga A  Hayakawa K 《Journal of agricultural and food chemistry》2007,55(16):6547-6552

Chiral resolution of isoxanthohumol (IX) in beer samples was performed by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. The optimum running conditions were found to be 20 mM phosphate buffer (pH 7.0) containing 45 mM hydroxypropyl-gamma-cyclodextrin and 100 mM sodium dodecyl sulfate with an effective voltage of +20 kV at 20 degrees C using direct detection at 210, 295, and 370 nm. IX was detected in 12 beer samples and the total levels of (+)- and (-)-IX ranged from 0.15 to 1.4 mg/L. But the amount of xanthohumol (XN) was below the detection limit (0.017 mg/L). Each level of (-)-IX was almost the same as that of (+)-IX, suggesting that IX was a racemic mixture in these beer samples. The racemization of IX in beer could be attributed to the production of a racemic mixture from XN during boiling and to the fact that IX enantiomers were easily interconverted.  相似文献   

随机森林在红松活立木腐朽分级中的应用     

谢军明  王立海  林文树  郝泉龄  解光强  孟庆凯  李怡娜  阚相成 《东北林业大学学报》2022,50(4):99-103+110

以五营森林公园中不同腐朽程度的红松为研究对象,选取无损、易获取指标(阻力损失及心材、边材异常面积比)为模型自变量,腐朽等级为因变量,利用无损检测并结合随机森林对活立木腐朽程度进行分级。使用重复分层K折交叉验证保证样本数据在训练和测试时分类均衡,并建立随机森林立木腐朽分级模型。结果表明：随机森林腐朽分级模型训练、测试精度分别为100%、90%,说明其拟合效果好、泛化能力强。随机森林对腐朽等级(Ⅰ、Ⅱ、Ⅳ、Ⅴ)的辨识均正确,召回率都为100%,腐朽等级Ⅲ错判1例,对腐朽立木进行分级的准确率高达96.67%,随机森林的微观、宏观平均AUC值分别为0.979 2、0.970 8。  相似文献   

不同安放角度对污水搅拌器水力特性的影响     

张海晟  郑源  张智  阚阚  莫旭颖 《排灌机械工程学报》2021,39(5):483-487

为深入对比污水处理池中搅拌器不同安放角度对其水力特性的影响,文中基于Fluent对搅拌器在不同安放角度下的水力特性进行数值模拟,得出适合搅拌器工作的较优工况.利用标准k-ε湍流模型及 SIMPLEC 算法对不同工况进行模拟,对比相应的流速分布和搅拌器中心所在平面的速度分量.结果表明:当搅拌器安放角度为-15°时,处理池内平均流速较高该工况下处理池内平均流速较高且搅拌器消耗的功率较小.通过分析搅拌器安放位置中心横断面的速度分量发现,经过搅拌器的水体呈现螺旋状向流向方向发展;在直角坐标系中3个方向速度分量各不相同.在搅拌器安放角度为-15°时,水体流速在轴y,z分量较大且不与墙体冲突.因此,在实际应用中适当改变搅拌器的安放角度,可以有效改善水体循环流动,优化搅拌器的搅拌效果,研究结果可为潜水搅拌器的实际工程提供参考.  相似文献   

Effect of improvement cutting on the community structure of aphyllophoraceous fungi on Okinawa Island     

Satoshi Yamashita  Tsutomu Hattori  Shin Abe  Hideaki Goto  Hiroki Sato 《Journal of Forest Research》2014,19(1):143-153

Improvement cutting, which decreases tree density by cutting and thinning while leaving logging residues, has been practiced on Okinawa Island since the 1970s and changes not only the vegetation composition but also the amount and composition of woody debris on the forest floor. To quantitatively compare the effect of improvement cutting with the effects of woody debris and vegetation on the community structure of aphyllophoraceous fungi, we conducted a field survey of vegetation composition, the amount and composition of woody debris, and the aphyllophoraceous fungi flora on Okinawa Island in December 2006. We established 3 plots in forest stands without logging and 13 plots in a forest that had undergone improvement cutting from 1 to 22 years before our field survey. The number and volume of woody debris tended to be highest soon after improvement cutting. We recorded 1,172 fungal samples belonging to 81 species in four orders. Fungal species richness was correlated with the composition of the woody debris. Fungal species composition in forest plots 1 year after improvement cutting differed from most of the other logged forests. Variation partitioning revealed that the effects of improvement cutting explained 14.1 % of the total variation in fungal species composition, and that differences in woody debris and vegetation not related to improvement cutting explained 40.4 %. Changes in the composition of woody debris caused by improvement cutting explained at most 2.7 % of the variation. This suggests that improvement cutting does not have a strong effect on fungal community structure, but woody debris does.  相似文献