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131.
【目的】从小尺度的斑块状栖息地角度出发分析高原鼠兔干扰及不同干扰强度对植被覆盖区土壤有机碳(SOC)、全氮(STN)和全磷(STP)含量的影响,有助于全面理解小型食草动物对草地土壤化学计量特征的影响。【方法】以高原鼠兔为研究对象,测定高原鼠兔栖息地及栖息地不同植被覆盖区土壤的 SOC、STN、STP 含量及土壤 C∶N∶P 化学计量特征的变化。【结果】与未干扰植被覆盖区相比,高原鼠兔栖息地植被覆盖区的 STN 含量和 N∶P 显著下降(P<0. 05),C∶N 显著增加(P<0. 05),但 SOC 和 STP 含量及 C∶P 没有发生显著变化;STN 和 SOC 含量、C∶P 和 N∶P 在高原鼠兔干扰最大的核心区最低,干扰强度最小的边缘区最高;C∶N 在干扰强度适中的次核心区最高,边缘区最低;而 STP 含量在不同干扰强度的植被覆盖区没有显著差异。【结论】高原鼠兔干扰及干扰强度会对其领地内植被覆盖区的土壤化学计量特征产生影响。高原鼠兔斑块状栖息地中土壤化学计量特征的变化可能是影响植物丰富度的因素之一。 相似文献
132.
Based on the content of enterprise culture and enterprise credit, it is pointed out that the enterprise culture related to the enterprise core competitive force.In this paper, from the viewpoint of combining theory with practice, the intension, function and mutual relations between them are described and their significance in the market competition as well.The potential things,which the enterprise staffs are seeking for, from its inherent mind and the enterprise theory are the enterprise culture which becomes the enterprise core competitive force in its actual sense.The enterprise credit, as the enterprise culture in its ideological sphere, is an essential factor, which greatly affects the enterprise core competitive force.At last the authors provide some good suggestions on how to cultivate enterprise credit and to build enterprise culture. 相似文献
133.
Condition assessment on power transformer is an important approach to improve reliability of transformer and provide proper decision-making for condition-based maintenance. For long, static assessment method used in the past has already not adapted to the development of modem electricity transmission and distribution technology. So based on the deficiency of fuzzy synthetic assessment method, matter-element synthetic assessment method is introduced. The method can evaluate transformer condition not only in quality but also in quantity. Because each index weight can be given fairly and fast through improved analytic hierarchy process, which need not carry on consistency chec accuracy of assessment can be improved. Examples analysis has proved that assessment method of power transformer condition based on matter-element theory is rational and effective. 相似文献
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烟草成分对其品质影响程度的粗糙集判别方法 总被引:8,自引:0,他引:8
运用粗糙集理论研究了烟草主要化学成分 (总糖、还原糖、总氮、烟碱、氧化钾和氯离子 )对烟草品质影响程度的判别方法。对比已有的研究结果 ,表明基于粗糙集理论的计算方法简单 ,结果明了 ,而且还能量化烟草成分对品质的影响程度。 相似文献
137.
ZHANG Qiong WAN Chang-wu YU Yan-ni XIA-Bing LIU Jiang-jin ZHANG Qiao-jun LI Zhu WANG Cheng-fei DAI Jia-lin WANG Jie 《园艺学报》2021,36(12):2133-2138
AIM To explore the possible mechanism of cathepsin C (CTSC) and tumor necrosis factor-α (TNF-α) in coronary heart disease (CHD) by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees (P <0.05). The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group (P <0.05). Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group (P <0.05). The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD (r2 =0.743, P <0.05). CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD. 相似文献
138.
E Yong BIAN Wei SHAN Dexin ZHANG Di FU Chunlei 《东北农业大学学报(英文版)》2006,13(2):149-152
Sludge is produced wherever sewage purification takes place. The amount of municipal dry sludge in China is more than 5.0×106 t per year. There are lots of soil nutrients, such as nitrogen, phosphorus and or- ganic matters contained in sludge, but heavy … 相似文献
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柑橘全爪螨是一种世界性害螨, 目前对许多药剂已经产生抗性。药剂复配是治理抗性问题, 延长药剂使用寿命的重要手段。为筛选出增效明显的复配新产品, 本文选取联苯肼酯作为标准药剂, 与阿维菌素和氟啶胺分别进行复配, 并采用叶碟喷雾法测定其联合毒力及增效作用。结果表明, 联苯肼酯、阿维菌素和氟啶胺的单剂LC50分别为16.43、0.29 mg/L和12.63 mg/L。联苯肼酯与阿维菌素复配比例为19∶1和15∶5的共毒系数分别为135.02和158.40, 具有增效作用。联苯肼酯与氟啶胺在6∶4、7∶3、5∶5、9∶1、8∶2复配比例的共毒系数分别为466.28、410.61、370.22、311.15和275.85, 增效作用显著。 相似文献