War and Love in A Farewell to Arms

Ernest Hemingway,the famous American writer,was one of the representatives of "the lost generation". He was good at depicting the life and the inner world of "the lost generation" ,especially the youth. A Farewell to Arms is one of his masterpieces. Because of the similarities between the hero and Hemingway himself,many critics regard it as an autobiographical novel. The novel develops with the themes of war and love,exposing the brutality and absurdity of World War I,and the unforgettable pain it caused. At the same time,Hemingway extolled beautiful and unselfish love. In an age filled with war and chaos,pure love served as a beacon in the darkness,bringing hope,comfort and courage to people.

Nutrient Content in Soils and Adaptability of Corn in Yuanzhou District,Guyuan City

[Objective] The aim was to research rational fertilization of corn in Yuanzhou District, Guyuan, Ningxia Hui Autonomous Region. [Method] Nutrient con- tents in soils in Yuanzhou District were measured with conventional analysis method and the suitable fertilization scheme of corn growth was proposed based on fertiliz- er-application rule of corn growth and nutrient balance. [Result] Soil in farmlands in Yuanzhou District was of alkalinity; organic matter, N, P and Zn were shortage; S was extremely insufficient; Fe and Mn were moderate; K was abundant; Cu would satisfy crop growth, [Conclusion] The research provides references for yield increase, reduction of chemical fertilizer and related pollution for corn growth.

Effects of Different Herbicides on Maize Growth and Weed Control in Maize Fields

Effects of four herbicides(paraquat, acetochlor, nicosulfuron and atrazine) on the growth of maize and control effect of plant quantity and fresh weight of weeds were studied. The results showed that 15 days after spraying the herbicides on weeds,the prevention and control effect of paraquat on weeds was the optimum, and its effects on the plant quantity and fresh weight of weeds were above 81.57%; the prevention and control effect of acetochlor on weeds was the second best; the prevention and control effect of atrazine on weeds was the worst, and its effects on the plant quantity and fresh weight of weeds were only 51.04% and 37.86%. After 30 or 45 days, the prevention and control effect of atrazine and nicosulfuron on weeds in the maize fields was better than the other herbicides, and their effects on the plant quantity and fresh weight of weeds were higher than 70.00% and 85.00%. Acetochlor and paraquat had certain phytotoxicity to the growth of maize after about 15 days, and its leaves became yellow and grew slowly. On the whole, nicosulfuron had good prevention and control effect on weeds and had no phytotoxicity to the growth of maize.

Soil Air Regime of Corn Field Under Plastic Mnlching

The effects of plastic inulching on soil aeralion at the soil dcpth uf 0-100 cm were studied in a corn tield.The resnlts indicated that the CO_2 concentration of unmulched soil in the 0-100 cm layer layer ranged from 0.00 1to 0.016 m￣3/m￣3, and that of mulched soil 0.002 to 0.018m￣3/m￣3, about 32.39% higher than the forrner on theaverage. Such a CO_2 concentration in the soil air is still suitable for crop growth. The O_2 concentration wasinversely correlated with CO_2 concentrat ion in the soil air ( unmulching r=-0.92￣(**), mulching r=-0. 79￣*). O_2concentration ranged from 0. 1 1 to 0. 17 m￣3/m￣3 in the mulched soil and 0. 1 3 to 0. 18 m￣3 /m￣3 in the unmulchedsoil. By contrast, N_2 concentration in soil air remained relatively steady, with no difference between the twotreatments. The relationship between the soil respiratory intensity and the depth of a soil layer appeared tobe a power function. At the layer of 0-20 cm, the soil respiration intensity in the mulched soil was obviouslyhigher than that in the unmulched. Plastic mulching could also affect soil structure. In comparison withthe unmulched soil, the content of >0.25 mm aggregate and 0.05-0.001 mm microaggregate in the mulched soil was reduced by 82.1% and 35.8%, respectively; the soil total porosity, gaseous phase rate and aerationporosity in the depth of 10-20 cm were reduced by 2.85%, 19.89% and 26.54% respectively, but contrary at the depth of 0-10 cm.

Management Options and Soil Types Differentially Affect Weeds in Maize Fields of Kakamega, Western Kenya

Maize production in Kenya is constrained by weed infestation and nutrient deficiencies. Field studies were conducted during the 2008/2009 cropping seasons to investigate weeds in maize fields on three dominant soil types in Western Kenya. Weeds were inventoried and their composition was compared using Jaccard＇s index. The economic importance of weed species （potential to reduce yields and the difficulty to control them by manual weeding） was assessed through participatory surveys. Finally, field trials assessed the effects of management options （farmer＇s practice, clean weeding, green manure, zero-tillage ＋ cover crop and zero-tillage） on weed biomass and species composition. Across the three soil types, 55 weed species in 21 families were identified. Soil types influenced species composition as confirmed by Jaccard＇s similarity indices of 0.50, 0.58 and 0.62 for Nitisol vs. Acrisol, Ferralsol vs. Acrisol and Nitisol vs. Ferralsol, respectively. The economically important weeds were Commelina benghalensis, Cynodon nlemfuensis, Bidens pilosa, Galinsoga parviflora and Leonotis nepetifolia. Management options significantly （P 〈 0.05） reduced weed biomass, irrespective of soil type and seasons. Maize biomass response was highest （7-16 Mg ha1） in zero-tillage and zero-tillage ＋ cover crop and lowest （2-8 Mg ha1） in farmer＇s practice. Significantly negative relationships （P 〈 0.01, r2 = 0.37 - 0.51） were established between leaf area index of maize and weed biomass across the soils. Zero-tillage combined with the use of a cover crop had the lowest weed biomass （〈 30% of the farmer practice） and thus appears to be a promising strategy combining soil fertility improvement with weed suppression in smallholder maize farming systems of Western Kenya.

Control Effect of 80% Nicosulfuron·Atrazine Water-dispersible Granules on Weeds in Spring Maize Field

[Objective] This study aimed to investigate the control effect of different concentrations of 80% nicosulfuron·atrazine water-dispersible granules on weeds in spring maize field. [Method] Maize field was sprayed with 300, 375, 450, 750 g/hm280% nicosulfuron·atrazine water-dispersible granules respectively, with 40 g/L nicosulfuron suspending concentrate and 38% atrazine suspending concentrate as control agents. Artificial weeding and control(CK) plots were set. [Result] Fresh weight control efficiency of 375-750 g/hm280% nicosulfuron·atrazine water-dispersible granules was significantly higher than that of 40 g/L nicosulfuron suspending concentrate and 38% atrazine suspending concentrate; no obvious phytotoxicity symptoms were observed after application of 300-450 g/hm280% nicosulfuron·atrazine waterdispersible granules; 750 g/hm280% nicosulfuron·atrazine water-dispersible granules posed certain impact on the growth of maize seedlings. Compared with control plots, various doses of 80% nicosulfuron·atrazine water-dispersible granules significantly improved the yield of maize. [Conclusion] In the present study, 375-450 g/hm280% nicosulfuron·atrazine water-dispersible granules exhibited high control effect on weeds in maize field and were safe for the growth of maize seedlings.

Taguchi-Optimized Catalytic Growth of Carbon Nanotubes for Applications in Electro-Catalysis

Taguchi method, largely used to optimize processes controlled by manifold parameters, has been utilized to improve the synthesis of carbon nanotubes by chemical vapor deposition of isobutane. Analyzing results obtained in nine suitably designed reactions, the influence of synthesis （773-973 K）, calcinations （723-1,023 K） and reduction （773-973 K） temperatures and catalyst-support （alumina, magnesia or Na＋-exchanged K10 clay） on specific yield and crystallization degree （i.e., C sp2 content） of the nanotubes has been ranked. After critical examination and adjusting of conditions predicted to give optimal results, -50 g of nanotubes per gram of metal are obtained at 973 K over Fe/alumina catalysts calcined at 723 K and reduced at 773 K. Under the same conditions, highly crystallized nanotubes （with 73% of C sp2 bonds, as qualitatively estimated from Raman spectroscopy）, suitable for electro-catalysis applications, are synthesized over Fe/clay catalysts.

Chinese Athlete Breaks 110-meter Hurdles World Record

Liu Xiang of China set a world mark in the 110-meter hurdles on July 12, breaking the record he shared with Britain’s Colin Jackson. Liu’s time of 12.88 seconds at the IAAF Super Grand Prix athletics meeting in Laussane, Switzerland was 0.03 better than the record he matched in winning gold at the 2004 Athens Olympics.

Emergy assessment of three home courtyard agriculture production systems in Tibet Autonomous Region, China

Home courtyard agriculture is an important model of agricultural production on the Tibetan plateau. Be- cause of the sensitive and fragile plateau environment, it needs to have optimal performance characteristics, including high sustainability, low environmental pressure, and high economic benefit. Emergy analysis is a promising tool for evaluation of the environmental-economic performance of these production systems. In this study, emergy analysis was used to evaluate three courtyard agricultural production models： Raising Geese in Corn Fields （RGICF）, Con- ventional Corn Planting （CCP）, and Pea-Wheat Rotation （PWR）. The results showed that the RGICF model produced greater economic benefits, and had higher sustainability, lower environmental pressure, and higher product safety than the CCP and PWR models. The emergy yield ratio （EYR） and emergy self-support ratio （ESR） of RGICF were 0.66 and 0.11, respectively, lower than those of the CCP production model, and 0.99 and 0.08, respectively, lower than those of the PWR production model. The impact of RGICF （1.45） on the environment was lower than that of CCP （2.26） and PWR （2.46）. The emergy sustainable indices （ESIs） of RGICF were 1.07 and 1.02 times higher than those of CCP and PWR, respectively. With regard to the emergy index of product safety （EIPS）, RGICF had a higher safety index than those of CCP and PWR. Overall, our results suggest that the RGICF model is advantageous and provides higher environmental benefits than the CCP and PWR systems.

Diurnal variation of ozone flux over corn field in Northwestern Shandong Plain of China

High concentration ground-level ozone(O3)has adverse effects on plant growth and photosynthesis.Compared to the O3concentration-based index,the O3flux-based(especially stomatal O3uptake)index has been considered the better criterion for assessing the impact of ozone on vegetation and ecosystems.This paper reports on a study of O3flux using the eddy covariance technique over a corn field in the Northwestern Shandong Plain of China.Diurnal variation of atmospheric O3concentration,deposition velocity and flux,and their relationships to environmental factors are analyzed.The results show that:(1)During the observation period(9 August–28 September,2011),there was a strong diurnal variation of O3concentration,with low(16.5 nL L?1)and high(60.1 nL L?1)O3mean concentrations observed around 6:30 and 16:00,respectively.Mean O3concentrations during daytime(6:00–18:00)and nighttime(18:00–6:00)were 39.8±23.1 and 20.7±14.1 nL L?1(mean±std),respectively.The maximum observed concentration was 97.5 nL L?1.The concentration was mainly affected by solar radiation and air temperature.(2)Whether daytime or nighttime,ground-level O3flux is always downward.The diurnal course of mean deposition velocity was divided into 4 phases:a low and stable process during nighttime,fast increasing in early morning,relatively large and steady changes around noon,and quickly decreasing in later afternoon.Daytime and nighttime mean deposition velocities were 0.29 and 0.09 cm s?1,respectively.The maximum deposition velocity was 0.81 cm s?1.The magnitude of deposition velocity was influenced by the corn growth period,and its diurnal variation was significantly correlated with global radiation and relative humidity.(3)O3flux was affected by variations of both O3concentration and deposition velocity,with mean O3fluxes-317.7 and?70.2 ng m?2s?1during daytime and nighttime,respectively.There was strong correlation between O3flux and CO2flux or latent heat flux.By comparing the deposition velocities of daytime and nighttime,we infer that stomatal uptake was probably the main sink of ground-level O3.

Soil Organic Carbon Loss and Turnover Resulting from Forest Conversion to Maize Fields in Eastern Thailand

Soil organic carbon(SOC) content and its stable carbon isotopic composition(within the upper 1 m) were measured to determine the e?ect of land-use changes from dry evergreen forest to maize fields in eastern Thailand.Digital land cover maps,derived from aerial photography and satellite images for years 1989,1996,and 2002 were used in association with field surveys and farmer interviews to derive land-use history and to assist in study site selection.Conversion from forest to maize cultivation for the duration of 12 years reduced SOC stocks at the rate of 6.97 Mg C ha-1 year-1.Reduction was most pronounced in the top 10 cm soil layer,which was 47% after 12 years of cultivation.Stable carbon isotope data revealed that the main fraction lost was forest-derived C.Generally low input rates of maize-derived C were not sufficient to maintain SOC at the level prior to forest conversion.After 12 years of continuous maize cultivation,the maize-derived C fraction made up about 20% of total SOC(5 Mg ha-1 of the total 25.31 Mg ha-1).

Diffusivity Models and Greenhouse Gases Fluxes from a Forest,Pasture,Grassland and Corn Field in Northern Hokkaido,Japan

Information on the most influential factors determining gas flux from soils is needed in predictive models for greenhouse gases emissions. We conducted an intensive soil and air sampling along a 2 000 m transect extending from a forest, pasture, grassland and corn field in Shizunai, Hokkaido （Japan）, measured CO2, CH4, N20 and NO fluxes and calculated soil bulk density （Pb）, air-filled porosity （fa） and total porosity （Ф）. Using diffusivity models based on either fa alone or on a combination of fa and 4, we predicted two pore space indices： the relative gas diffusion coefficient （Ds/Do） and the pore tortuosity factor （T）. The relationships between pore space indices （Ds/Do and T） and C02, CH4, N2O and NO fluxes were also studied. Results showed that the grassland had the highest Pb while fa and Ф were the highest in the forest. CO2, CH4, N20 and NO fluxes were the highest in the grassland while N20 dominated in the corn field. Few correlations existed between fa, Ф, Pb and gases fluxes while all models predicted that Ds/Do and T significantly correlated with CO2 and CH4 with correlation coefficient （r） ranging from 0.20 to 0.80. Overall, diffusivity models based on fa alone gave higher Ds/Do, lower τ, and higher R2 and better explained the relationship between pore space indices （Ds/Do and τ） and gases fluxes. Inclusion of Ds/Do and τ in predictive models will improve our understanding of the dynamics of greenhouse gas fluxes from soils. Ds/Do and τ can be easily obtained by measurements of soil air and water and existing diffusivity models.

Responses of Different Physiological Indices for Maize(Zea mays) to Soil Water Availability

Knowledge of plant responses to soil water availability is essential for the development of effcient irrigation strategies.However,notably different results have been obtained in the past on the responses of various physiological indices for different plants to soil water availability.In this study,the responses of various plant processes to soil water availability were compared with data from pot and field plot experiments conducted on maize(Zea mays L.).Consistent results were obtained between pot and field plot experiments for the responses of various relative plant indices to changes in the fraction of available soil water(FASW).A threshold value,where the relative plant indices began to decrease with soil drying,and a lower water limit,where the decline of relative plant indices changed to a very slow rate,were found.Evaporative demand not only influenced the transpiration rate over a daily scale but also determined the difference in transpirational response to soil water availability among the transient,daily and seasonal time scales.At the seasonal scale,cumulative transpiration decreased linearly with soil drying,but the decrease of transpiration from FASW = 1 in response to water deficits did not affect dry weight until FASW = 0.75.On the other hand,the decrease in dry weight was comparable with plant height and leaf area.Therefore,the plant responses to soil water availability were notably different among various plant indices of maize and were influenced by the weather conditions.