高产环境下水稻精确定量栽培技术初探

以4个高产水稻品种为材料在云南省永胜县涛源乡进行精确定量栽培研究。结果表明，不同品种的总叶龄数不同，但差异较小。在理想气候的条件下，基础产量为10．5t／hm^3，基础供氮量120—165kg／hm^2。按精确定量技术栽培的水稻产量都在16t／hm^2，明显比常规栽培法增产，并能省工节本。使用精确定量栽培技术，涛源水稻还有较大的增产潜力。

高产环境下韩国粳稻与云南粳稻主要性状的对比研究

在玉溪水稻高产栽培环境下,对引进的75个韩国水稻材料的经济性状与本地75个水稻材料进行对比研究。结果表明,韩国水稻材料分蘖力较强,结实率不高,但生育期偏短,穗型偏小,千粒重不高,因此,难于直接应用于生产,但大多数韩国水稻材料的米粒透明度要好于当地材料。研究结果为利用韩国水稻材料的优异性状改造本地品种(材料)提供了理论依据。

Environmental change and its effects on inter-decadal variations of diatom production, species composition and frustule dissolution in a coastal marginal sea

The implications of climate change during the second half of the 20th century have been reported throughout the world. Although marginal seas are sensitive to climate change and anthropogenic impacts, relatively little attention has been given to the South East Asian marginal seas. Thus, to bridge this gap in knowledge, a sediment core was collected from the coastal areas of the Leizhou Peninsula in the South China Sea （SCS） to study the inter-decadal climate change and its consequences using diatom species composition as a proxy record. Diatom absolute abundance varied from 2 300 to 68 000 and averaged 16 000 valves per gram of dry weight （v/gdw）. The fractional dissolution index （F~） was usually below 0.5, which indicates low to moderate preservation of diatom valves at coastal area of the SCS. At the inter-decadal time scale, total diatom abundance was high for the period after 1972, which coincided with 1） increased percentage of planktonic diatom abundance and F~; 2） emergence and dominance of high productivity indicative cosmopolitan species such as Thalassionema nitzschioides and Paralia sulcata （their relative abundance increased from 〈1.5% to 〉7% for the period before and after 1972, respectively）; 3） decreased relative abundance of the small-sized eutrophication indicative species, Cyclotella striata, from 70% to 40%. This study reveals that variations in the abundance of diatoms preserved in the sediment was a function of both production and dissolution/preservation of diatom valves, which in turn was intimately connected to the prevailing environmental/climatic conditions. In conclusion, these data reveal the existence of substantial changes in the coastal SCS in response to the 1970s climate shift that was recorded in different parts of the world.

Urea Preparation by Oxidative Carbonylation of Ammonia

Effective one-stage method of urea preparation by catalytic oxidative carbonylation of ammonia in liquid phase is developed. The method allows to prepare urea with productivity of-530 g/（L·h） in sufficiently mild conditions （total pressure -30 bar, 45 ℃）. The process is characterized by high selectivity （near 100%） i.e. byproducts separation is not needed. Almost all CO is consumed during the process, this substantially diminishes the waste-gas purification costs and raises the process environmental characteristics; the only byproduct is water.

Environmental Impact of Climate Change on Agricultural Production in Ekiti State, Nigeria

Climate change will impact agriculture and food production around the world due to the effects of elevated CO2 in the atmosphere, higher temperature, altered precipitation and transpiration regimes, increased frequency of extreme events, and modified weed, pest and pathogen pressure. Data of this study were collected from primary and secondary sources. Primary sources of data were collected using two sets of structured questionnaires. A total number of three hundred （300） questionnaires were administered on categories of respondents in this study. Results of this study revealed that food crops are the major crops cultivated in the study area, and the effects of climate change on agricultural production results in soil loss, plant nutrient loss, textural change, increase in pest and diseases and poor yield germination etc.. This study therefore recommended that cover trees should be planted, which will provide shade and reduce heat, due to climate change and the preservation of underground water.

An Innovative City： Impact of Innovations on City Development

The process of innovative development is stimulated by cities as centers of accumulated （regional） growth and innovative enterprises as elements of urban space. Cities stimulate innovations by creating a specific demand for innovations and innovative products as well as specific incentives such as preferable conditions for creation, accumulation, usage, and exchange of knowledge and information. Diffusion of ideas has an impact on changes in environment resulting in increase in dynamics of innovation, which means possibilities of innovative development for local firms. The paper highlights the idea of an innovative city with respect to the impact of innovations on city development. The concept of an innovative city is not clearly defined because the interpretation of innovation is differentiated and ambiguous except for common denominator of the novelty. The paper underlines the role of city＇s environment for innovations＇ creation acting as an incubator for clusters of firms, particularly those engaged in the process of high-tech involvement （technology parks）. The option of an innovative city approach presented here is the author＇s view on an innovative city＇s growth and it is based on the role of synergic interaction between innovative firms as elements of a city space and an innovative city itself.

High-Volume Fly Ash Concrete-A Relevant Step to Sustainable Development

HVFA （high-volume fly ash） concrete could be a sustainable way for by-product utilization to conserve natural resources and protect environment. HVFA concrete can play the role of a high-performance material that may be comparable to the conventional Portland cement concrete. The results of the research programme concerning the relationships between the composition of concrete （w/b ratio, fly ash content and type of cement） and their physical and mechanical properties are presented and discussed in the paper. It is found that the introduction of high-volume fly ash into concrete has caused a decrease in compressive strength at the early age of storage. The significant increase in strength was observed between 28 days and 90 days of curing. The high-volume fly ash concretes were characterized with lower water absorbability and sorptivity than control concrete.

Characteristics of ion debris from laser-produced tin plasma and mitigation of energetic ions by ambient gas

Extreme ultraviolet lithography is most promising for the next generation lithography. However, debris from laser-produced plasma, particularly energetic ions, severely decreases the lifetime of extreme ultraviolet optics. We measured the characteris- tics of ions from tin plasma by the time of flight method with a frequency-doubled Nd： YAG laser at the intensity of 3.5x1010 W/cm2 （532 nm, 8 ns）. Our measurement shows that the maximum and peak of tin ions energies from plasma under the above experimental parameters are about 4.2 and 1.8 keV, respectively. Moreover, it is found that kinetic energy angular distribution of tin ions can be fitted by cos0.8（θ）, where θ is the angle with respect to the target normal. We also investigated the mitigation effect of argon, helium gases to the tin ions, and found that tin ions from the plasma can be mitigated effectively at the pressure -38 mTorr for argon or -375 mTorr for helium, respectively.