[目的]了解国际科技期刊在开放评议和双盲评议方面的实践,探索这两种评议方式的优缺点及对科技期刊质量控制的价值.[方法]对国际科技期刊实行开放评议和双盲评议的案例进行调研,如BMC系列期刊、F1000 Research、Nature 系列期刊等.[结果]有越来越多的期刊在尝试这两种方式,它们在减少传统单盲评议的偏见方面发挥了一定作用,但也带来了新的问题.[结论]开放评议和双盲评议适合于不同类型的期刊.期刊应根据自身的学科特点、学术定位来选择适合自己的同行评议方式,并在实践中不断评估,对之进行适当的调整.

In order to understand the adsorption characteristics of ciprofloxacin in ustic cambosols, static adsorption experiments were used to investigate dynamic and isothermal adsorption characteristics of ciprofloxacin in ustic cambosols, influence of pH on the adsorption process. Results showed that the absorption process of ciprofloxacin can be divided into two stages: fast adsorption and slow balance. The adsorption processes followed the pseudo-second-order kinetics, with adsorption rate of 1.138 x 10(-3) - 2.849 x 10(-2) kg x (min x mg)(-1). Adsorption isotherms of ciprofloxacin in ustic cambosols were well described by the Freundlich and Langmuir equation, Freundlich equation is more applicable than Langmuir equation, with the adsorption capacity (lgKf) of 2.725. Moreover, at the tested pH interval of 4-9, lgKd values of ciprofloxacin increased and then decreased with the increase of pH in ustic cambosols; the maximum adsorption of ciprofloxacin in ustic cambosols can be obtained when the pH value was 5 with lgKd value was 3.11; strong acid or alkali conditions were unfavorable to ciprofloxacin adsorption. It could be deduced that cationic adsorptions was one of the significant sorption mechanisms for ciprofloxacin in ustic cambosols.

散养是白洋淀地区养鸭的主要方式,散养过程中产生的大量鸭粪因不够集中、难以收集而残留于土壤表面.借助小区模拟试验,研究了白洋淀雨季(6～9月份)残留在土壤表面的鸭粪中氮素动态变化及环境影响因素.结果表明:鸭粪中部分氮素以NH3的形式挥发.挥发期为45 d左右,挥发量约为8.72 kg·hm-2;NH3挥发主要集中在鸭粪排出后的7d内,挥发初期随温度降低、湿度增加和光照减弱逐渐降低,随着挥发的减弱其与环境因素相关性不明显.模拟小区地表径流中总氮(TN)流失负荷为10.05 kg·hm-2,以颗粒态氮(PN)为主;可溶态氮(TDN)中,以无机氮为主.淋溶水中总氮淋失负荷为19.30 kg·hm-2,以NO-3-N为主.自然状态下,鸭粪中约10%氮素以NH3挥发、地表径流和淋溶流失;部分氮素残留于土壤中,另有部分未矿化鸭粪存在于土壤表面,约占鸭粪总量的45.09%.残留于土壤中的氮素一旦达到土壤临界值,将威胁当地水环境安全,因此必须采取有效措施,防止养鸭带来的过量氮素累积造成的环境污染.

This study focused on temporal-spatial variability of nitrogen concentration in surface water of paddy field in Xinzhuang town,Changshu city of Taihu region,and made a strategic decision for controlling nitrogen pollution.Afterthe application of base and panicle fertilizer on the 2nd,4th,6th,8th day and tillering fertilizer on the 2nd,5th,7th,9th day,120 samples were taken from the area of 120 m2 paddy field and then variability of concentration of total-N,ammonium-N(NH4+-N),nitrate-N(NO3——N) was analyzed with chemical and geostatistical method.The results showed different trends of concentration of three nitrogen.In this experimental condition,if drainage was arranged on the 8th day after fertilization,there would be a higher pollution risk for tillering fertilizer than base fertilizer and a least risk for panicle fertilizer.Characteristics of three nitrogen spatial distribution indicated medium spatial correlation degree.Concentration of nitrogen in surface water gradually increased from east plot to west plot.It probably ascribed to water leakage on the eastern side and flow direction(from east to west).Therefore,the earliest drainage is advised to be resorted in ecological ponds,subsequently to be purified before flowing into stream to reduce risk of nitrogen pollution of water body.

The misalignment-induced aberrations by corrector and the support of the asphere were analyzed in this paper.A computed-aided alignment method was presented combining the interferometric test with the computer optimization for optical alignment,and a mathematical model was established to determine the misalignment.The simulated and actual experimental results of the alignment show that after four times alignment the test results of the asphere can reach up to 0.028λ(RMS)(λ=632.8 nm).

Terrestrial transect is an important and effective method for global change study. The Northeast China Transect (NECT), which is assigned along the latitude 43 degrees 30'N in the mid-latitude of temperate zone and located at 112 degrees-130 degrees 30'E and 42-46 degrees N, is one of the fifteen global transects recognized by IGBP. It is about 1600 km in length and 300 km in width. The NECT is mainly driven by precipitation, and becomes an effective platform of global change study in China. Based on the field survey in 2001 and a simulated experiment, this paper analyzed the gradient distribution of soil nitrogen and its response to climate change along the Transect. The results indicated that soil total and available nitrogen in NECT were significantly related to longitude, with a correlation coefficient being 0.695 (P < 0.001) and 0. 636 (P < 0.001), respectively, and had a similar horizontal distribution with soil organic carbon. Soil available nitrogen content in the NECT was decreased from east to west, and could be one of factors restricting plant growth. The decreasing rate of soil total and available nitrogen from topsoil to subsoil was different with ecosystems along the NECT. Soil total and available nitrogen contents had a close linear relationship with soil pH, total and labile carbon, total and available phosphorus, total sulphur, total and available zinc, available potassium, available manganese, bulk density, water holding capacity, and total porosity. They also had a significant linear relationship with precipitation, the correlation coefficient being 0.682 (P < 0.001) and 0.688 (P < 0.001), respectively. The short-term simulated experiment showed that doubled ambient CO2 concentration and soil moisture regime had no significant effects on soil total and available nitrogen, the variation coefficients being 5.55% and 3.84%, respectively.

研究了施用玉米残体对土壤有机氮组分特征的影响.结果表明:与对照相比,玉米残体(秸秆和根茬)配施化学氮肥,可增加玉米生育前期土壤酸解氨态氮和氨基糖氮含量及整个生育期内土壤酸解氨基酸氮的含量;与单施氮肥相比,可增加玉米整个生育期内土壤酸解氨基糖氮和氨基酸氮含量,同时对酸解未知氮亦产生不同的影响.玉米残体还田改变了土壤有机氮的分布.玉米整个生育期间土壤酸解未知氮的变异系数在土壤有机氮组分中最大,它在土壤供氮潜力中的作用仍需深入研究.

Terrestrial transects have become an important and effective method for the study of global change. The Northeast China Transect (NECT) is one of the fifteen global transects recognized by IGBP, which is assigned along the latitude 43°30′ N in the mid_latitude of the temperate zone, located between longitude 112°-130°30′ E, latitude 42°-46° N. It is about 1 600 km in length and 300 km in width. NECT is mainly driven by precipitation, and has become an effective platform of global change study in China. Soil labile carbon is a very dynamic proportion of soil organic carbon. In this paper, we got soil labile carbon by oxidation of potassium permanganate. Based on the data from the field survey in 2001 along NECT and a simulated experiment, the distribution of soil labile carbon along the Northeast China Transect (NECT) and its responses to climatic change were analyzed. The results indicated that the average of soil labile carbon was (3.52±0.881) g·kg -1 accounting for 13.1%±0.78% of soil organic carbon along the NECT. The values of soil labile carbon were (10.88±2.236) g·kg -1 in longitude 126°-131°, (1.35±0.327) g·kg -1 in longitude 119°-126°, (2.07±0.342) g·kg -1 in longitude 113°-119° and (0.51±0.216) g·kg -1 in longitude 111°-113°. Soil labile carbon was significantly related to soil organic carbon (R=0.993, p 0.001). They had a similar trend of the horizontal distribution. The range of decease of soil labile carbon in depth was bigger than that of soil organic carbon. The content of soil labile carbon had a close linear relationship with soil pH, soil total nitrogen, soil total phosphorus, soil total sulphur, soil total zinc, soil available nitrogen, soil available phosphorus, soil available potassium, soil available manganese, soil available zinc, soil bulk density, water holding capacity, and soil total porosity. The soil labile carbon had a significant linear relationship with precipitation. Its correlation coefficient was 0.712 (p0.001) and more than soil organic carbon's (R=0.677 p0.001). In the short_term simulated experiment, the coefficient of variation of soil organic carbon was 1.28%. Coefficient of variation of soil labile carbon was 29.67%. Soil labile carbon was relatively more sensitive to doubled CO 2 content and different soil moistures. The variation of soil labile carbon resulting from different soil moistures was reduced with doubled CO 2 content. Thus, it is very important to understand the state and availability of soil organic carbon in the carbon cycle study.

采用盆栽试验和 15N示踪技术对玉米生长期间不同施肥处理黑土土壤微生物量氮的动态变化及其与土壤氮素组分、玉米吸氮量之间的关系进行研究.结果表明,在玉米生长期间,施肥并没有影响土壤微生物量氮的变化趋势,但不同施肥处理土壤微生物量氮的含量明显不同.玉米植株残体的加入,增加了土壤微生物量氮的数量,降低了土壤微生物对肥料 15N的释放率.土壤微生物量氮与土壤全氮含量呈极显著的正相关(r＝0.727**),与土壤碱解氮及玉米吸氮量之间均呈显著正相关(相关系数分别为0.528*和0.536*).土壤微生物量氮和土壤氮素组分对作物吸氮量的通径分析表明,土壤微生物量氮的有效性近于土壤矿质态氮、高于土壤酸解有机氮和非酸解氮.土壤微生物量氮是作物吸收氮素的有效来源.

Based on field micro-plot experiment, the effects of corn stalk and stubble remained in field on soil biochemical factors were discussed. The results indicated that corn stalk and stubble rationing application of N fertilizer would increase the content of soil microbial biomass carbon. Soil pH buffer capacity was strengthened. Soil aggregate structure was improved. Corn stalk and stubble remained in field would be helpful to maintenance and liberation of soil available nutrients( N, P, K, Cu, Zn, Fe and Mn) .