新04号泉溶解气氢气异常特征分析

选取乌鲁木齐周围100 km范围内MS4地震和300 km范围内MS≥5地震,分析新04号泉氢气资料。结果显示,新04号泉对乌鲁木齐周围100 km范围内4级地震无明显震兆异常,对300 km范围内MS≥5地震对应情况较好,对应率为80%。     

S210线芦山-宝兴段崩塌灾害危险性分析及防治对策建议

＂4·20＂芦山地震发生后,作为进出地震灾区的生命线工程省道S210芦山-宝兴段多处发生崩塌滚石等次生地质灾害,堵断交通,威胁来往群众的生命安全,严重影响了抗震救灾和灾后的恢复重建。通过对此路段进行崩塌灾害现场考察,得出此路段的崩塌灾害多发生在大于40°的坡体上,坡向为SW、W和NW,易发岩性为灰岩、砂岩、白云岩和砾岩,切割深度多大于16m。通过GIS进行因子叠加分析,将此路段划分为3级危险度区域,并根据芦山地震灾区崩塌滚石灾害成因机制、分布与活动特征、成灾方式与危害对象,提出了相应的防治对策与建议。     

Study of initial vorticity forcing for block onset by a 4-dimensional variational approach

With the aid of a global barotropic model, the role of the interaction of the synoptic-scale disturbance and the planetary flow in block onset is examined by a 4-dimensional variational approach. A cost function is defined to measure the squared errors of the forecasted stream functions during block onset period (day 4 and day 5 in this study) over a selected blocking domain. The sensitivity of block onset with respect to the initial synoptic-scale disturbance is studied by examining the gradient of the defined cost function with respect to the initial (during the first 24 hours) vorticity forcing, which is evaluated by the adjoint integration. Furthermore, the calculated cost function and gradient are connected with the limited-memory quasi-Newton optimization algorithm for solving the optimal initial vorticity forcing for block onset. For two studied cases of block onset (northern Atlantic and northern Pacific) introducing the optimal initial vorticity forcing, the nonlinear barotropic advection process mostly reconstructs these blocking onset processes. The results show that the formation of blocking can be correctly described by a barotropic nonlinear advection process, in which the wave- (synoptic-scale) flow (planetary-scale) interaction plays a very important role. On an appropriate planetary-scale flow, a certain synoptic-scale disturbance can cause the blocking onset by the interaction between the synoptic scale perturbations and the planetary scale basic flows. The extended forecasts show that the introduction of the optimal initial vorticity forcing can predict the blocking process up to the 7th or 8th day in this simple model case. The experimental results in this study show that the 4-dimensional variational approach has a good potential to be applied to study the dynamics of the medium-range weather processes. This simple model case study is only an initial trial. Applying the framework in this study to a complex model will further our understanding of the mechanism of the atmospheric/oceanic processes and improve their prediction.     

4DSVD分析误差与样本选取方法和样本容量的关系初探

分析误差与样本选取方法和样本容量的关系是4DSVD同化方法一个亟需研究的重要问题。获得支撑大气模式空间和观测空间吸引子的基向量是4DSVD研究的关键部分,样本的好坏和样本容量的范围是决定4DSVD基向量和分析结果质量的一个重要前提条件。首先利用Lorenz28变量模式,用4DSVD方法做了一些简单三维同化试验,探讨了Lorenz28变量模式的分析误差与样本容量和样本选取方法的关系。数值试验结果表明,对一个具体的模式,有限的样本容量就能够获得较高精度的分析结果;在模式系统和观测系统不变情况下,用一定样本容量得到的支撑模式空间和观测空间的基向量具有很好的稳定性,即一旦获得一组较好的基向量,在观测系统和模式系统不变的情况下,对同化任何时刻的观测适用;分析结果对选取方法没有太大的依赖性,但具体的样本容量要视不同模式和样本选取方法而定。用WRF模式做的4DSVD四维观测系统模拟试验结果表明,若样本选取方法得当,所需要的样本容量要远远小于模式自由度。4DSVD要真正获得较高精度的分析结果,需要的条件是尽可能的在吸引子上取样并选取充足的样本容量;间隔取样可以一定程度上减少计算量。根据数值试验结果提出了4DSVD在实际同化时样本选取的一些初步的方法。     

卫星导航定位技术在C4ISR中的应用

介绍了世界上的几种全球卫星导航定位系统的特点和C4ISR系统对导航定位技术的需求,以及组合导航系统在C4ISR系统中的应用。分析了卫星导航定位作为C4ISR系统关键技术发挥的重要作用,指出了卫星导航定位是C4ISR系统综合一体化的关键技术。     

最近13万年以来洛川黄土剖面中固定铵态氮的古气候意义

对13万年以来洛川黄土-古土壤序列中固定铵态氮进行了分析.末次间冰期S1古土壤中固定铵态氮含量最高,其次为冰后期S0古土壤,末次冰期形成的马兰黄土最低;而且,固定铵态氮的分布在马兰黄土中也能体现出三次小的低-高值的波动特征.洛川黄土13万年以来固定铵态氮的分布与磁化率和<2μm组分的分布相似.在此基础上,利用马兰黄土中粒度与固定铵态氮的相关关系,计算了S1古土壤中固定铵的分布,并与实测结果进行了对比,推测S1古土壤中固定铵态氮有轻微的损失,尽管如此,S1古土壤中固定铵态氮含量仍然高于黄土.鉴于黄土-古土壤序列中固定铵态氮的分布与粉尘粒度有密切的关系,能与气候变化较好地对应,它可视为反映黄土高原区东亚冬季风强-弱周期性变化较好的替代性指标.     

新疆阿尔泰金矿带主要金矿类型、成矿规律及成矿预测

新疆阿尔泰金矿带金矿分布广泛,主要类型有火山晚期热液型金矿床、与韧性剪切带有关的金矿床.对不同类型金矿床基本成矿特征进行了研究,探讨了不同类型金矿床的控矿作用,在此基础上总结了阿尔泰金矿带主要金矿类型的成矿规律,对主要金矿深部进行了成矿预测,发现并圈出了矿床深部的矿化异常.     

Chemical and spectroscopic characterization of dissolved humic substances in a mangrove-fringed estuary in the eastern coast of Hainan Island, China

Mangrove-derived dissolved organic matter(DOM) has an important effect on estuarine and coastal area on a large scale.In order to improve the understanding of origin,composition,and fate of DOM in mangrove-fringed estuarine and coastal areas,dissolved humic substances(DHS) were isolated from one mangrove pore-water sample and one near-shore seawater sample downstream the mangrove pore-water site in the eastern coast of Hainan Island,South China.Fulvic acids,humic acids and XAD-4 fractions were obtained from the two water samples by using a two-column array of XAD-8 and XAD-4 resins.Chemical and spectroscopic methods were used to analyze the features of these DHS.Compared to the mangrove pore-water DHS,the near-shore seawater DHS were found rich in 13 C with lower C/N ratios and more aliphatic compounds and carbohydrates,but less aromatic structures and carboxyl groups.As for the three fractions of the two DHS,XAD-4 fractions contain more aliphatics,carbohydrates,carboxyl groups,and enrich in 13 C with respect to both fulvic and humic acids.Photo-oxidation transformation and contribution from marine-derived DOM were considered as the main reasons resulted in the difference in compositional features for these DHS in this study.     

Effects of exposure to four endocrine disrupting-chemicals on fertilization and embryonic development of Barbel chub (Squaliobarbus curriculus)

The toxicities of 4 common endocrine-disrupting chemicals (EDCs), 17β-estradiol (E2), p,p′-dichlorodiphenyldichloro-ethylene (DDE), 4-nonylphenol (NP) and tributyltin (TBT), to sperm motility, fertilization rate, hatching rate and embryonic development of Barbel chub (Squaliobarbus curriculus) were investigated in this study. The duration of sperm motility was significantly shortened by exposure to the EDCs at the threshold concentrations of 10 ng L^?1 for E2 and TBT, 1 μg L^?1 for NP and 100 μg L^?1 for DDE, respectively. The fertilization rate was substantially reduced by the EDCs at the lowest observable effect concentrations (LOECs) of 10 ng L^?1 for E2 and TBT and 10 μg L^?1 for DDE and NP, respectively. Of the tested properties of S. curriculus, larval deformity rate was most sensitive to EDC exposure and was significantly increased by DDE at the lowest experimental level of 0.1 μg L^?1. Other EDCs increased the larval deformity rate at the LOECs of 1 ng L^?1 for E2, 10 ng L^?1 for TBT and 1 μg L^?1 for NP, respectively. Despite their decreases with the increasing EDC concentrations, the hatching rate and larval survival rate of S. curriculus were not significantly affected by the exposure to EDCs. The results indicated that all the 4 EDCs affected significantly and negatively the early life stages of the freshwater fish S. curriculus. Overall, E2 and TBT were more toxic than NP and DDE, while DDE might be more toxic to larval deformity rate than to other measured parameters. Thus, the 4 EDCs showed potential negative influences on natural population dynamics of S. curriculus. Our findings provided valuable basic data for the ecological risk assessment of E2, DDE, NP and TBT.     

2007年宁洱6.4级地震序列精定位

Five mobile digital seismic stations were set up by the Earthquake Administration of Yunnan Province near the epicenter of the main shock after the Ning’er M6.4 earthquake on June 3, 2007. In this paper, the aftershock sequence of the Ning’er M6.4 earthquake is relocated by using the double difference earthquake location method. The data is from the 5 mobile digital seismic stations and the permanent Simao seismic station. The results show that the length of the aftershock sequence is 40km and the width is 30km, concentrated obviously at the lateral displacement area between the Pu’er fault and the NNE-trending faults, with the majority occurring on the Pu’er fault around the main shock. The depths of aftershocks are from 2km to 12km, and the predominant distribution is in the depth of 8～10km. The mean depth is 7.9km. The seismic fault dips to the northwest revealed from the profile parallel to this aftershock sequence, which is identical to the dip of the secondary fault of the NE-trending Menglian-Mojiang fault in the earthquake area. There are more earthquakes concentrated in the northwest segment than in the southeast segment, which is perhaps related to the underground medium and faults. The depth profile of the earthquake sequence shows that the relocated earthquakes are mainly located near the Pu’er fault and the seismic faults dip to the southwest, consistent with the dip of the west branch of the Pu’er fault. In all, the fault strike revealed by earthquake relocations matches well with the strike in the focal mechanism solutions. The main shock is in the top of the aftershock sequence and the aftershocks are symmetrically distributed, showing that faulting was complete in both the NE and SW directions.