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91.
采用大系统仿真的建模方法,将油船各个液货舱气相区作为节点置于液货气相管网中,构建一个大系统。在对液货气相管网采用管网有限元方法进行稳态建模和对油船所有液货舱气相区作为变质量系统实行动态建模的基础上,采用预报校正法来离散一阶非线性方程组,并根据工况特征来选择时间步长实现实时仿真各种液货作业中涉及船舶安全的液货舱气相区和气体管网系统中压力、温度、烃气浓度和氧浓度等舱气物性参数的动态变化。仿真结果符合客观实际并通过实测数据得到了验证。仿真研究为油船液货舱气相区乃至整个液货舱的状态控制和液货作业优化提供了理论依据和途径。 相似文献
92.
从利率市场化的国际经验来看,无论是在发达国家还是发展中国家,其实施过程都容易导致不同程度的银行业危机。采用1973~2012年42个国家的面板数据,对利率市场化背景下的银行业危机进行的实证研究表明:利率市场化的推进将增加银行系统性危机发生的机率,特别是在存款利率市场化阶段,而严格的银行监管是抑制银行系统危机发生的有效方法;显性存款保险制度的设立无助于利率市场化后银行系统性风险的防范,甚至有可能会增加危机发生的机率;资本账户开放下进行利率市场化会增加银行系统危机发生的机率。利率市场化进程中允许开设民营银行不会增加银行系统危机的发生机率。 相似文献
93.
BTH诱导橡胶抗炭疽病效果初探 总被引:1,自引:0,他引:1
用化学诱导剂BTH(benzothiadiazole)处理橡胶叶片后,再接种橡胶炭疽病菌,以研究BTH诱发橡胶对炭疽病产生系统性抗性的能力。结果表明,用BTH处理古铜期橡胶叶片后,橡胶炭疽病的病情指数较对照显著降低,BTH诱发橡胶叶片对炭疽病产生抗性的最佳浓度为200 mg/L,处理后7 d表现出最佳诱导抗性。说明BTH可以诱导橡胶对炭疽病产生系统获得抗性,并可用于田间炭疽病防治。 相似文献
94.
Systematical regulation involved in heterogeneous photosynthetic characteristics of individual leaf in pima cotton 下载免费PDF全文
ZHANG Yu-jie HAN Ji-mei LEI Zhang-ying MENG Hao-feng ZHANG Wang-feng ZHANG Ya-li 《农业科学学报》2022,21(4):995-1003
Light heterogeneity leads to anatomically and physiologically heterogeneous features in leaves. However, little attention has been paid to the effects of nonuniform illumination on the anatomical and photosynthetic performance on both sides along the leaf main vein. This study explored such effects by combining in situ determination in the field with shading simulation in the phytotron, on pima cotton that has cupping leaves. Photosynthetic characteristics and morphological structures were measu... 相似文献
95.
Abstract Several chemicals including the strobilurins (trifloxystrobin, azoxystrobin, pyraclostrobin and DPX KZ 165), a plant activator (acibenzolar), the triazoles (propiconazole, tebuconazole, epoxiconazole, fenbuconazole and JAU 6475) and tridemorph, spiroxamine, pyrimethanil, fenarimol and various formulations of mancozeb were evaluated in three field experiments in northern Queensland, Australia for control of yellow Sigatoka of banana (caused by Mycosphaerella musicola). In all experiments, the strobilurins used alone or in spray programs with mancozeb and acibenzolar were as effective or better than the industry standards mancozeb and propiconazole. Acibenzolar used in spray programs with mancozeb significantly improved the control of Sigatoka compared to mancozeb alone. The triazoles, epoxiconazole, fenbuconazole and JAU 6476 used alone and tebuconazole in a spray program with mancozeb were as effective as the industry standard propiconazole. Tridemorph, pyrimethanil and spiroxamine were as effective as the industry standard mancozeb, and fenarimol failed to effectively control the disease. In 2004, trifloxystrobin, pyraclostrobin and epoxiconazole were registered for control of yellow Sigatoka of banana. 相似文献
96.
The phenolic ester 3-0-trans-p-coumaroyltormentic acid and the volatile compounds (E,E)-α-farnesene and methyl salicylate have been identified previously in pear tree cultivars ‘Bartlett,’ ‘NY10355,’ and ‘Conference.’ Here, using the same dried extract of leaf samples, the contents of total protein, chlorophyll, and the minerals calcium (Ca), magnesium (Mg), phosphorus (P), potassium (K), sodium (Na), carbon (C), and nitrogen (N) were determined. Differences between pear cultivars were found with regard to their absolute content in Ca, K, chlorophyll, and total protein, and to carbon/nitrogen values in uninfested leaves compared with leaves infested by Cacopsylla pyricola (Foester) and C. pyri L. (Homoptera, Psyllidae) on partially and completely infested trees. The ratio of nutrients and minerals to the constitutive and Cacopsylla-induced phenolic and two volatiles reflects a diminution of the leaf quality as food for Cacopsylla nymphs in infested leaves of all cultivars. In uninfested leaves, the magnitude of this ratio in partially infested trees of cv. ‘Conference’ with local response, together with Ca ion content and chlorophyll loss, point to classification of this cultivar as tolerant to herbivory. 相似文献
97.
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99.
[目的]研究生防枯草芽孢杆菌Czk1对橡胶树体内防御酶活性的影响,探讨其诱导橡胶树抗病性机理,为Czk1在生物防治领域的应用打下基础.[方法]以过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)5种防御酶作为植物抗病性反应指标,用Czk1菌株发酵液1倍原液及10、100倍稀释液喷洒处理橡胶叶片,以喷洒LB液体培养基为对照,于不同时段测定各防御酶活性;按照生防菌与炭疽病菌接种顺序的不同,测定橡胶树炭疽病菌及生防菌对橡胶植株抗性相关酶活性的影响.[结果]经Czk1发酵液10倍稀释液处理的橡胶树叶片中CAT、POD、PAL和PPO 4种酶活性最高,诱导植株抗病性效果最佳,各酶活峰值分别达4264.62、28946.18、186.67和53.70 U/g,为对照组的5.24、6.34、3.19和3.38倍;而叶片中SOD活性最高的为Czk1发酵液1倍原液处理组,酶活峰值为1344.53U/g,为对照组的5.19倍.先喷洒Czk1发酵液后接种病原菌的处理组,橡胶树叶片CAT、SOD、POD、PAL和PPO活性均显著高于其他处理组,各酶活峰值分别为4129.02、640.96、7416.94、173.35和71.59U/g,为对照组的4.20、2.08、2.50、2.56和7.64倍.[结论]喷施生防菌Czk1稀释液可促使橡胶树抗病相关酶活性升高,诱导橡胶植株产生系统抗性.诱导抗性可能是枯草芽孢杆菌防治橡胶树真菌病害的重要机制之一. 相似文献
100.
An 11-year-old Thoroughbred mare presented for evaluation of severe, acute bilateral epistaxis of several hours’ duration. Endoscopic evaluation revealed active haemorrhage from the right guttural pouch and significant dorsal compression of the nasopharynx. Rapid and severe retropharyngeal swelling developed, prompting placement of a temporary tracheostomy. Guttural pouch mycosis was suspected and transarterial coil embolisation of the right internal carotid, external carotid and maxillary arteries was successfully performed. It was suspected that haemorrhage from the vasculature of the guttural pouch tracked caudally into the retropharyngeal region resulting in significant swelling, pharyngeal collapse and a severely compromised airway. Clinicians should be aware of this rare complication of guttural pouch epistaxis. 相似文献