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971.
We developed a process model of flame beam transmission using pulverized coal powder and coke combustion in a raceway. We employed a Monte Carlo computation method equation based on charge couple devrce(CCD) target heat flow distribution for radiation heat transfer. We explored the factors impacting radiation transmission. Based on these, a three dimensional reconstruction was analyzed at varying coke particle concentrations. This model provided an effective method to produce on line monitoring of raceway working states. 相似文献
972.
We investigated the removal effects of chloride ion on treating organic substances with electrolysis using leachate from semi aerobic bioreactors. The experimental results show that, under the given conditions, the removal efficiency of refractory organic substances increases with rising initial chloride ion concentration in leachate. The impact of chloride ion on removal efficiency mainly is influenced by the initial chloride ion concentration and the chemical oxygen demand (COD) in leachate. The impact of chloride ion on the specific electric consumption of removal COD is obvious when the initial chloride ion concentration is lower. No obvious change of this impact is observed when the chloride ion concentration exceeds 125 g/L. Meanwhile, the more obvious impact of initial chloride ion concentration on organic substance removal is observed when the COD concentration in leachate is lower. 相似文献
973.
NaCl、单Na+、Cl-胁迫对不同番茄幼苗光合特性的影响 总被引:3,自引:1,他引:3
为探讨番茄耐性品种的生理机制,以醋栗番茄、辽园多丽、红宝石和辽园红玛瑙4种不同基因型番茄为试材,比较研究了50,100,150 mmol/L的NaCl及等渗150 mmol/L单Cl-、单Na+溶液胁迫,对番茄苗期相对生长量、盐害指数、叶绿素含量、光合作用的影响.结果表明:随着盐浓度增加,4种番茄幼苗的地上部相对干鲜质量、相对株高、相对叶片数、光合色素含量、叶片净光合速率、气孔导度、蒸腾速率逐渐降低,盐害指数逐渐升高;通过各项指标鉴定醋栗番茄、辽园红玛瑙耐盐性大于辽园多丽、红宝石;等渗的NaCl及其单离子Na+、Cl-胁迫,Cl-离子伤害最小,Na+离子对番茄的毒害比Cl-离子敏感;4种番茄在50 mmol/L NaCl胁迫下光合速率降低的主要原因是气孔因素限制,其他高盐浓度胁迫则为非气孔因素限制. 相似文献
974.
番茄幼苗叶绿素荧光参数对水分胁迫的响应 总被引:3,自引:1,他引:3
以5叶1心期番茄品种‘辽园多丽’为试材,研究番茄幼苗叶绿素荧光特性、叶绿素含量以及叶片相对含水量对水分胁迫的生理响应。结果表明,水分胁迫导致叶绿素荧光参数Fv/Fm、qL、ETR下降,NPQ上升;在轻度水分胁迫下,叶绿素荧光各参数值均有突跃现象。在整个水分胁迫过程中番茄幼苗叶片相对含水量及叶绿素含量均呈下降趋势。NPQ与基质含水量的变化密切相关,相关系数为-0.83,表明荧光参数NPQ可以作为指导灌溉的一个指标。当NPQ为2.0975时,基质含水量降到31.2%,番茄幼苗生长受到水分胁迫的影响,应及时灌溉。 相似文献
975.
野生百合种类稀少,个别种类是中国特有,植物离体快速繁殖是保护稀少濒危百合种的有效方法,本研究为了探究一种朝鲜百合快速繁殖的方法。本研究以野生百合朝鲜为试材,以MS培养基为基础培养基,附加不同种类和浓度的植物生长调节物质(6-BA,NAA)诱导丛生芽及再生植株。以朝鲜百合的鳞茎为外植体,确定鳞茎的最佳消毒时间、影响鳞茎芽诱导的最佳激素组合以及不同激素对鳞茎芽增殖的影响。结果表明:最佳灭菌时间为0.1% HgCl消毒10 min;由于内源激素比例不同,鳞茎诱导的最佳培养基为MS+6-BA 1.0 mg/L+NAA 0.2 mg/L;最佳继代培养基为MS+6-BA 1.0 mg/L+NAA 0.1 mg/L;最佳增殖培养基为MS+6-BA 1.0 mg/L+NAA 0.15 mg/L。 相似文献
976.
The finite element of a prestressed concrete (PSC) beam is analyzed in a case of diverse prestressing forces. The mechanical model applied is that advanced by Clough for a concrete beam bearing axial force. The results indicate that the beam frequencies decrease with increasing prestressing force. A dynamic experiment of a non bonded PSC beam was carried out to validate the veracity of the finite element analysis. Test beam frequencies increase with increasing prestressing force. The analysis model thus is unfit for frequency analysis of a PSC beam. The determinant factor of frequencies is analyzed, and the dynamic model is modified according to experimental results. The modified model analysis result shows that: the calculated frequencies of mode 1 agree with the test results well; the frequencies of mode 2 posses some errors; and, the modified model can reflect the direction of frequency change along with the change of prestressing force well. 相似文献
977.
Since P. R. China has experienced extensive land resource use, environmental degradation, lagging rural development and other difficulties in 20th century, urban countryside integration and ecological planning has become an important subject to build a harmonious society in the 21st century. The country attempted to use complexity science and ecological thinking based on recognizing the relationship between the city and countryside and raising the city countryside space ecology coupling concept to construct a city countryside space planning methods system consisting of the identification of urban and rural land uses, urban and rural non construction land planning, city countryside coupled environmental conditions assessment, coordinated city countryside space development and city countryside space system fractal optimization, and more. 相似文献
978.
Utilizing the self made unit body model test apparatus, the deformation laws of backfill grouting were studied under different grouting pressures, different soil conditions and different ground water pressures. It was shown that high grout pressures can accelerate the consolidation rate of grout drainage and increase final deformation amount. And soil permeability coefficient was an important factor to grout deformation. The ground water pressure was more important for sand soil while the grout pressure was for clay soil. The proposed apparatus can truly reflect stress status of grout injected to tail void. And grout deformation properties were helpful to clarify the stratum stress release and stratum deformation of backfill grouting. 相似文献
979.
We present an aeroelastic model design and method creation based on the case of an ±800 kV ultra high voltage (UHV) power transmission line from Xiang Jiaba to Shanghai, P. R. Chin, Both the centralized and discreted stiffness modeling methods are unsuitable for tower aeroelastic modeling. Taking these stiffness and aerodynamic characteristics into account, we introduce a new method to create an aeroelastic model that includes a semi rigid model segment and U shaped springs. Because the span of this transmission line is too long to fit within the wind tunnel in the same proportions as the tower, the proportions of the line model is condensed further. Aeroelastic test requirements can be satisfied by comparing theoretical analysis and actual measurements of the system model dynamics. 相似文献
980.
The type and percentage of sand affect the gradation of coarse fine aggregate and the amount of spare mortar in concrete, which further affects the resistance of fresh concrete to initial plastic shrinkage. Taking into account the engineering characteristics of sand in the area of Chongqing, P. R. China, three fine aggregates composed of superfine, medium, mixed and manufactured sand, are used to prepare high performance concrete (HPC). The effects of these three fine aggregates on initial plastic shrinkage crack are investigated. The results show that the HPC prepared with superfine sand possesses a higher initial shrinkage value than HPC prepared with mixed or medium sand. An optimal sand percentage is necessary to reduce the initial shrinkage cracking of HPC prepared with mixed or medium sand. 相似文献