mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Pyrolysis Mechanism of Hemicellulose Monosaccharides in Different Catalytic Processes

The pyrolysis behaviors of four different hemicellulose monosaccharides, namely, two pentoses (xylose and arabinose) and two hexoses (mannose and galactose) catalyzed by HZSM-5 were investigated. The effects of two different processes by which the catalyst comes into contact with the substrate, namely, mixed with monosaccharide (in-bed) or layered above monosaccharide (in situ), were compared. Evolution characteristics of typical pyrolytic products (H_2O, CO_2, acids, furans and aromatics) were achieved by thermogravimetry-Fourier transform infrared spectroscopy. The in-bed catalytic process significantly lowered the pyrolytic temperature and increased the production of furans and acids at a low temperature by enhancing dehydration, retro-aldol fragmentation and Grob fragmentation. During the in situ catalytic process, volatiles generated from monosaccharides passed through a catalyst bed and underwent further dehydration, decarboxylation, and decarbonylation, significantly lowering the yields of acids and furans. The yield of aromatics was enhanced, and the corresponding volatilization temperature was lowered, especially under the in-bed catalytic conditions. Pentoses entered into the zeolite pores more easily than hexoses did because of their smaller molecular size; thus, the in-bed catalytic process drastically affected pentose pyrolysis.
超声弹性成像在鉴别甲状腺微小结节中的价值

实时超声弹性成像是近年来发展起来的一种新的超声显像技术,其通过检测施加外部压力所致组织变形和扭曲的程度来反映被检测组织的硬度。本研究旨在探讨实时超声弹性成像对TI-RADS评分4级的最大直径≤10 mm的甲状腺单发实性微小结节良恶性的鉴别诊断价值,以提高术前超声诊断正确率。
Suppression of Fusarium Wilt of Banana with Application of Bio-Organic Fertilizers

Fusarium wilt is one of the most serious diseases of banana plants caused by soil-borne pathogen Fusarium oxysporum f.sp. cubense (FOC). In this study a pot experiment was conducted to evaluate the effects of different bio-organic fertilizers (BIOs) on Fusarium wilt of banana, including the investigations of disease incidence, chitinase and β-1,3-glucanase activities of banana plants, and FOC populations as well as soil rhizosphere microbial community. Five fertilization treatments were considered, including chemical fertilizer containing the same N, P and K concentrations as the BIO (control), and matured compost mixed with antagonists Paenibacillus polymyxa SQR-21 and Trichoderma harzianum T37 (BIO1), Bacillus amyloliquefaciens N6 (BIO2), Bacillus subtilis N11 (BIO3), and the combination of N6 and N11 (BIO4). The results indicated that the application of BIOs significantly decreased the incidence rate of Fusarium wilt by up to 80% compared with the control. BIOs also significantly promoted plant growth, and increased chitinase and β-1,3-glucanase activities by 55%–65% and 17.3%–120.1%, respectively, in the banana roots. The population of FOC in the rhizosphere soil was decreased significantly to about 10~4 colony forming units g~(–1) with treatment of BIOs. Serial dilution plating and denaturing gradient gel electrophoresis analysis revealed that the application of BIOs increased the densities of bacteria and actinomycetes but decreased the number of fungi in the rhizosphere soil. In general, the application of BIOs revealed a great potential for the control of Fusarium wilt disease of banana plants.
Effect of Nitrogen Starvation on the Responses of Two Rice Cultivars to Nitrate Uptake and Utilization

Ammonium (NH_4~+) is the main nitrogen (N) form for rice crops, while NH_4~+ near the root surface can be oxidized to nitrate (NO_3~-) by NH_4~+ -oxidizing bacteria. Nitrate can be accumulated within rice tissues and reused when N supply is insufficient. We compared the remobilization of NO_3~- stored in the tissue and vacuolar between two rice (Oryza sativa L.) cultivars, Yangdao 6 (YD6, indica) with a high N use efficiency (NUE) and Wuyujing 3 (WYJ3, japonica) with a low NUE and measured the uptake of NO_3~-, expression of nitrate reductase (NR), NO_3~- transporter genes (NRTs), and NR activity after 4 d of N starvation following 7-d cultivation in a solution containing 2.86 mmol L~(–1) NO_3~-. The results showed that both tissue NO_3~- concentration and vacuolar NO_3~- activity were higher in YD6 than WYJ3 under N starvation. YD6 showed a 2- to 3-fold higher expression of OsNRT2.1 in roots on the 1st and 4th day of N starvation and had significantly higher values of NO_3~- uptake (maximum uptake velocity, V_(max)) than the cultivar WYJ3. Furthermore, YD6 had significantly higher leaf and root maximum NR activity (NR_(Amax)) and actual NR activity (NRA_(act)) as well as stronger root expression of the two NR genes after the 1st day of N starvation. There were no significant differences in NRA_(max) and NRA_(act) between the two rice cultivars on the 4th day of N starvation. The results suggested that YD6 had stronger NRA under N starvation, which might result in better NO_3~- re-utilization from the vacuole, and higher capacity for NO_3~- uptake and use, potentially explaining the higher NUE of YD6 compared with WYJ3.
Effects of Urea and Controlled Release Urea Fertilizers on Methane Emission from Paddy Fields: A Multi-Year Field Study

A four-year (2008–2011) field study was implemented in a major rice-growing region of China to better understand the effect of urea and controlled release fertilier (CRF, thermoplastic resin-coated urea in this study) on CH_4 emission from paddy fields. Over the four years, the average CH_4 emission during the rice growing seasons was 76.9, 65.8 and 64.9 kg CH_4 ha~(–1) in treatments CK (zero N), U (urea) and C (CRF), respectively. Urea and CRF significantly reduced CH_4 emission by 14.4% and 15.6%, and increased average rice grain yield by 25.8% and 19.7% (P < 0.05), respectively, compared with treatment CK. Flooding duration would affect CRF’s effect on CH_4 emission from paddy fields. Under normal aeration conditions, CH_4 emission tended to be 3.9%–15.2% lower in treatment C than in treatment U from 2009 to 2011, while it tended to be 4.2% higher under delayed aeration conditions in 2008. The findings suggest that mid-season aeration (MSA) starting on D30 (30 days after rice transplanting), just like the local practice, would optimize the CRF’s effect on CH_4 emission from rice fields in China. Over the four years, average rice yield did not differ between treatments U and C, and tended to be 5% lower in treatment C than in treatment U.
Soils and Surface Waters as Affected by Long-Term Swine Slurry Application in Oxisols of Southern Brazil

The accelerated expansion of swine production in Brazil has increased the generation of liquid wastes, which are usually applied to agricultural soils after a simplified treatment and pose potential environmental impacts. The objective of this study was to assess the agronomic and environmental impacts of long-term application of swine slurry (SS) on soil and stream water properties in watersheds dominated by Oxisols in Quinze de Novembro of Southern Brazil. Soil samples (0–30 cm) were collected from farms with continuous application of SS since 1990 at low (40–80 m~3 SS ha~(–1) year~(–1)) and high (120–300 m~3 SS ha~(–1) year~(–1)) rates of SS. Surface water samples were collected from streams adjacent to the farm fields. Long-term SS application did not change total organic C and particulate organic C compared to cropland and woodland soils without SS application. The high rates of SS increased total N, P, Cu, and Zn and available P and Cu in the topsoil (0–10 cm) compared to woodland and cropland soils without SS application. Surface water analyses showed that fecal coliform bacteria and biological oxygen demand exceeded the legal limits for high quality water (Class 1). Other water parameters (such as NO_3~-, phosphate and total suspended solids) were within the acceptable limits. Long-term disposal of SS in cropland under no-tillage had impaired water quality in Quinze de Novembro, especially biological parameters. Some best management practices should be adopted, including more rigorous control of SS application to cropland as well as requiring edge-of-field and riparian vegetative buffers.
调肝通脉汤消退冠状动脉粥样硬化斑块探讨

介绍运用调肝通脉汤消退冠状动脉粥样硬化斑块体会。认为冠心病粥样硬化斑块的形成与肝密切相关,肝伤则木病及火,心脉筋膜失养而受损,气滞血瘀阻于脉络,厚浊水谷精微积于脉络,而致冠状动脉粥样硬化斑块形成。基于此认识,提出疏肝补肝即调肝治法,拟方调肝通脉汤治疗。
张仲景附子用量探析

附子为临床常用中药之一,但其有大毒,用量不易掌握。追溯《伤寒杂病论》,探究张仲景附子的用量,发现其附子常用1枚,但1枚附子的实际重量目前观点尚未统一。通过文献研究考证,认为张仲景所用附子1枚重约6.9g,现代炮制附子多反复用水浸泡、高温水煮、高热爆炒,这是后世附子用量增大的原因。
6q24 transient neonatal diabetes mellitus: the first case report from China

To the editor: Neonatal diabetes mellitus (NDM) is one kind of monogenic diabetes which usually presents within 6 months after birth and needs insulin treatment for at least 2 weeks. For transient neonatal diabetes mellitus (TNDM), all patients will go into remission phase but nearly half the patients have the risk of developing diabetes again. About 70% of all TNDM is 6q24 TNDM, which is related to imprint disorder causing hypomethylation on chromosome 6q24. General progression and treatment are similar in 6q24 TNDM patients. Insulin treatment usually no more than 18 months is needed at presentation,and sulfonylureas (SUs) can be chosen during relapse. Out of rarity of the disease, until now no case report including detailed clinical data has ever been published before in China. Here we report the first case of 6q24 TNDM diagnosed as paternal uniparental disomy (patUPD),in which homologous chromosomes of chromosome 6 are both paternal origin, resulting from the mistake in meiosis or mitosis.
Magnetic resonance study of the structure and function of the hippocampus and amygdala in patients with depression

Background The hippocampus and amygdala exhibit structural and functional alterations in patients with depression. The objective of this study was to investigate the structural and functional relationships between these core regions.Methods Based on the severity of their condition, 60 patients and 20 healthy controls were equally divided into four groups (mild group, moderate group, major group and health controls group), scanned by T1-MR, functional magnetic resonance imaging (fMRI), and susceptibility weighted imaging (SWI). Structural image, BOLD image, and SWI image were collected for processing and analysis. The characteristics of the depression and controls were checked by analysis of variance test, and the difference between groups was checked by Dunnett’s test.Results The volume of hippocampus and amygdala varied with the severity of the condition. The signal obtained under the stimulation of negative events was linearly?decreased in the mild, moderate and major groups revealed by fMRI.The length and diameter of the lateral ventricle vein was reduced in the mild group, whereas the number of branches increased. In the moderate and major groups, the reduction in the length, diameter and increase in the number of branches of the lateral ventricle vein were greater.Conclusion The alterations of the volume, fMRI, and cerebral?veins in these core regions may account for the causal relationship between structure and function.
A case of tubulopapillary hidradenoma on the face

To the editor: In September 2013, a 60-year-old man presented to our department with a lesion on left face. The lesion was found about one year ago without previous trauma or any other reasons, and enlarged slowly accompanying occasional itch. The medical and family histories were unremarkable. On dermatological examination, a solitary red-brown colored, firm, non-tender, mobile nodule of 0.8 cm diameter was seen on the left face. The surface of the nodule was smooth (Figure 1A). Provisional diagnoses of fibroma or sebaceous cyst were made. The lesion was excised and sent for histopathological examination.
体外冲击波治疗肩关节周围炎的疗效观察

目的观察体外冲击波治疗肩关节周围炎的疗效。方法选取肩关节周围炎患者60例,按随机数字表法将其分为治疗组和对照组,每组30例。对照组采用传统推拿手法治疗,治疗组采用体外冲击波治疗。治疗7d、14d、21d及28d时,采用视觉模拟评分法(VAS)对患者的疼痛程度进行评定。治疗前及治疗结束后,采用美国肩肘外科医师评估表(ASES)对患者的肩关节功能进行评定。结果与组内治疗7d时比较,对照组治疗14d[(2.8±1.1)分]、21d[(4.8±1.6)分]、28d[(5.2±1.6)分]时的VAS评分差值较大,差异有统计学意义(P<0.05)。与组内治疗14d时比较,对照组治疗21d、28d时的VAS评分差值较大,差异有统计学意义(P<0.05)。与治疗组治疗后同时间点比较,对照组治疗7d、14d时的VAS评分差值较大,差异有统计学意义(P<0.05)。与组内治疗前比较,2组患者治疗后ASES评分均较高,差异有统计学意义(P<0.05)。与治疗组治疗后ASES评分[(85.17±0.40)分]比较,对照组ASES评分[(83.97±0.34)分]较低,但差异无统计学意义(P>0.05)。结论体外冲击波可有效缓解肩关节周围炎患者的疼痛症状,值得临床应用、推广。
PERSISTENCE AND EXTINCTION OF A STOCHASTIC LOGISTIC MODEL WITH DELAYS AND IMPULSIVE PERTURBATION

A stochastic logistic model with delays and impulsive perturbation is proposed and investigated. Sufficient conditions for extinction are established as well as nonpersistence in the mean, weak persistence and stochastic permanence. The threshold between weak persistence and extinction is obtained. Furthermore, the theoretical analysis results are also derivated with the help of numerical simulations.
Motion of a spherical particle in a fluid forced vortex by DQM and DTM

In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method (DTM) with the Pade approximation and the differential quadrature method (DQM). The significant contribution of the work is the introduction of two new,fast and efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy and minimal computational effort for studying the particle motion in a fluid forced vortex. In addition, the velocity profiles (angular and radial) and the position trajectory of a particle in a fluid forced vortex are described in the current study.
Process and cause of urban-rural development transformation in the Bohai Rim Region, China

China’s reform and opening-up policy has brought the country a great development opportunity. The high-speed growth of the economy not only led China to a period of industrialization, urbanization, informatization and agricultural modernization, but also exacerbated the situation of the urban-rural dual structure. Based on the review of current studies, we first used the analytic hierarchy process (AHP) method to evaluate the urban-rural development and transformation level by population transformation index, land transformation index, industrial transformation index and social transformation index between 1996 and 2012 around the Bohai Rim Region. Then, based on the results of each index, we used the exploratory spatial data analysis (ESDA) method to investigate the spatial autocorrelation of the change in the urban-rural development transformation index during the 16-year period using Global Moran’s I index and Local Moran’s I index. Finally, we investigated the mechanism of change of the urban-rural development transformation index at county level, summarizing five main factors: (1) the radiation from the surrounding big cities, (2) the acceleration of the urbanization process, (3) the upgrading of the industrial structure, (4) the publishing and implementation of a macro development strategy and regional policy, and (5) natural factors such as topology.
A quantitative morphometric comparison of cockpit and doline karst landforms

This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin (Guangxi, China), La Alianza (PR, USA), Avalton (KY, USA), and Oolitic (IN,USA). Five types of landform entities were defined: isolated hill (IH), clustered hills (CHs),isolated sinkhole (IS), clustered sinkholes (CSs), and clustered hills with sinkholes (CHSs).An algorithm was developed to automatically identify these types of landform entities by examining the contour lines on topographic maps of two cockpit karst areas (Guilin and La Alianza) and two doline karst areas (Oolitic and Avalton). Within each specific study area, the CHSs is the least developed type yet with a larger size and higher relief. The IH and IS entities are smaller in size, lower in relief, and outnumber their clustered counterparts. The total numbers of these types of entities are quite different in cockpit and doline karst areas. Doline karst is characterized by more negative (IS and CSs) than positive (IH and IHs) landforms and vice versa for cockpit karst. For example, the Guilin study area has 1192 positive land-form entities in total, which occupy 9.81% of the total study area. It has only 622 negative landform entities occupying only 3.91% of the total study area. By contrast, the doline karst in Oolitic has 130 negative while only 10 positive landform entities. The positive and negative landforms in Oolitic occupy 12.68% and 2.61% of the total study area, respectively. Furthermore, average relief and slope of the landform entities are much higher and steeper in the cockpit karst than the doline karst areas. For instance, the average slope of CHs in Alvaton is 3.90 degrees while it is 19.78 degrees in La Alianza. The average relief of CSs is 4.07 m and 34.29 m in Oolitic and Guilin respectively. Such a difference within a specific area or between the cockpit and doline karst may reveal different controls on the development of karst landscape.
Inter-annual variations in vegetation and their response to climatic factors in the upper catchments of the Yellow River from 2000 to 2010

To understand the variations in vegetation and their correlation with climate factors in the upper catchments of the Yellow River, China, Normalized Difference Vegetation Index (NDVI) time series data from 2000 to 2010 were collected based on the MOD13Q1 product.The coefficient of variation, Theil-Sen median trend analysis and the Mann-Kendall test were combined to investigate the volatility characteristic and trend characteristic of the vegetation.Climate data sets were then used to analyze the correlation between variations in vegetation and climate change. In terms of the temporal variations, the vegetation in this study area improved slightly from 2000 to 2010, although the volatility characteristic was larger in 2000-2005 than in 2006-2010. In terms of the spatial variation, vegetation which is relatively stable and has a significantly increasing trend accounts for the largest part of the study area.Its spatial distribution is highly correlated with altitude, which ranges from about 2000 to 3000 m in this area. Highly fluctuating vegetation and vegetation which showed a significantly decreasing trend were mostly distributed around the reservoirs and in the reaches of the river with hydropower developments. Vegetation with a relatively stable and significantly decreasing trend and vegetation with a highly fluctuating and significantly increasing trend are widely dispersed. With respect to the response of vegetation to climate change, about 20-30% of the vegetation has a significant correlation with climatic factors and the correlations in most areas are positive: regions with precipitation as the key influencing factor account for more than 10% of the area; regions with temperature as the key influencing factor account for less than 10% of the area; and regions with precipitation and temperature as the key influencing factors together account for about 5% of the total area. More than 70% of the vegetation has an insignificant correlation with climatic factors.
TCGA divides gastric cancer into four molecular subtypes:implications for individualized therapeutics

Gastric cancer is a leading cause of cancer deaths in the world. The treatment of gastric cancer is chalenging because of its highly heterogeneous etiology and clinical characteristics. Recent genomic and molecular characterization of gastric cancer, especialy the findings reported by the Cancer Genome Atlas (TCGA), have shed light on the heterogeneity and potential targeted therapeutics for four different subtypes of gastric cancer.
A Source for the Excellent Floating Ability of a Water Strider

A water strider’s floating mechanism is of significance for the design of new biomimetic robots. However, the explanation of this mechanism has not been fully comprehended due to a lack of effective experimental methods.We describe a novel transmission speckle correlation technique, which is used to determine the deformation of liquid surfaces caused by a resting water strider, as well as a calculation of the resulting forces in the vertical direction. Furthermore, the variation of the liquid surface morphology at different times in the process of a water strider being unconscious has been measured and analyzed. The results show that the wax material secreted by water striders is a vital source for the excellent floating ability of a water strider, and that the effective time of the wax is less than 2 h.
The Effect of the Semiconductive Screen on Space Charge Suppression in Cross-Linked Polyethylene

The space charge distributions of cross-linked polyethylene (XLPE) with Borouge’s Borlink? semiconductive screen type LE0550 and LE0595 from a pulsed electro-acoustic method are obtained. The contact interface morphology at the semiconductive screen and the structure of XLPE near the interface are characterized. The dielectric spectrum and the conductivity current of XLPE with the different semiconductive electrodes are compared. The semiconductive screen changes the structure and the dielectric characteristic of XLPE near the contact interface, which may be the main reason for space charge suppression in XLPE with Borouge’s type LE0550 semiconductive screen.
中国月平均气温可预报性的时空特征及其年代际变化

利用中国1960~2011年资料比较完整的518站逐日气温观测资料, 采用非线性局部 Lyapunov 指数(NLLE)和非线性误差增长理论, 定量分析了中国区域月时间尺度平均气温可预报性期限(MTPL)的时空分布和年代际变化特征. 分析发现: 多年平均的MTPL 空间分布存在明显的地域差异, 总体来看, 东北大部、云南西南部和西北地区东部为可预报性高值区, 长江中下游地区及黄淮流域为可预报性低值区; MTPL 在各月份的空间分布存在明显的季节变化, 总体上表现为冬半年可预报性较低, 而夏半年较高; MTPL 还具有明显的年代际变化特征, 就全国而言, 从1970年以来, MTPL 具有上升的趋势, 在2000年前后出现下降的趋势, 尤其是东北地区在1986年之后可预报性显著提高. 西北、黄淮、东北 MTPL 的年代际变化可能与气温的持续性有关. 进入21世纪, 除南方地区外, 大部分地区的MTPL 有降低趋势. 上述结果为进一步认识我国月尺度气温异常的机理奠定科学基础,并为提高月尺度气温预测能力提供参考.
我国典型沙漠(地)流动风沙土的深层渗漏量及动态变化

土壤水分是干旱生态系统的重要制约因素,一直是干旱区研究和生态建设的热点和难点问题,对降雨的深层土壤渗漏水量仍缺少定量观测研究.本文采用作者自主研发的YWB-01型土壤深层水分渗漏计量仪对毛乌素沙地等4大沙漠(地)的流动沙地测试记录了降雨入渗到150 cm以下深层土壤的渗漏水量,连续2年的资料表明:(1)降雨的深层渗漏水量自东向西由半干旱区向干旱区递减,其中:乌审旗流动沙地渗漏水总量高达508.4 mm,占同期降雨量58.4%,磴口的渗漏水量为23.8 mm,占降雨量13.9%,而阿拉善左旗和右旗未测试到渗漏水量,但≥25 mm的强降水对干旱和半干旱区流沙地深层土壤水分的渗漏补给具有重要作用;(2)渗漏水量的季节变化与降水的变化趋于一致,但有一定滞后,在降雨量较大地区,二者变化的相似性更强;(3)单次较强降雨在降雨开始的40~55 h后出现一个渗漏水量峰值,渗漏速率增加较快但其减少相对缓慢,持续渗漏过程长达150 h左右,降雨量越大,渗漏水量峰值就越高,渗漏水量所占降雨量的比例也越高;受降雨强度、雨量和历时的共同作用,就低强度、长历时和单次降雨量大的降雨事件更有利于降雨对沙地深层土壤的渗漏补给;(4)受土壤冻融作用的影响,在快速消融期3月份出现一个小的渗漏补给峰值.研究结果对我国干旱和半干旱区沙地水资源的准确评估和合理利用及生态建设具有现实指导意义.
1956~2010年中国可更新水资源量的变化

随着人类对水资源需求的增加,对生态和环境问题的日益重视,水资源安全问题越来越受到国际社会的广泛关注.水资源已成为制约中国经济社会可持续发展的瓶颈,已被提升到关系中国经济安全、生态安全和国家安全的战略高度.认识中国水资源的变化,对分析气候变化的影响,编制水资源利用和保护规划以及制定水资源政策具有重要的参考价值.结合中国水资源评价的资料成果,利用距平分析、Mann-Kendall趋势检验和Morlet小波分析,本文较全面地研究了1956~2010年我国水资源的变化.结果显示:(1)从全国尺度上,水资源变化趋势并不明显.近55年来我国水资源总量呈现微弱的增加趋势,近20年的年均水资源量比多年均水资源量仅增加1%.(2)我国不同水资源分区的水资源变化差异较大,我国北方地区海河区、黄河区的水资源显著减少,近20年减少幅度达19%和17%;而我国南方地区和西北地区水资源的增加,特别是西北诸河区,近20年该区水资源量增加近10%.(3)相对1961~1990年,近20年来全国水资源量的年际变化波动有增加趋势.在水资源一级区中西北诸河区和西南诸河区变差系数增加较明显,但在水资源量显著减少的海河区、黄河区年际变化趋于减小.(4)全国水资源变化存在14年准周期,其叠加了各水资源一级区水资源系列不同周期,相邻水资源一级区水资源变化的第一或第二主周期存在明显一致性.
两种形态分析方法对冰川退缩时间序列土壤中磷的生物有效性评价

土壤磷的生物有效性是陆地生态系统安全和初始生产力的重要影响因素.土壤中磷的生物有效性由其形态组成决定.常用的磷形态分类方法是Hedley提出的连续提取法,即通过不同化学强度的提取剂对土壤样品进行分步提取,各级提取剂提取出的磷被定义为不同形态的磷.近年来又推出了X射线吸收近边结构法(XANES),利用在分子水平上给出目标元素周围的局部结构和化学信息的优势,能区分出与Fe,Al和Ca等金属结合的磷的形态.本文利用改进的Hedley连续提取法和XANES方法对贡嘎山海螺沟冰川退缩迹地上土壤中磷的形态进行了分析,在比较两种方法优缺点的基础上,获得了海螺沟冰川退缩120年序列上土壤磷的生物有效性的变化.结果表明:Hedley连续提取法对即时生物可利用磷能有准确的判识(Resin-P和NaCHO_3-P),而XANES方法对金属结合态的磷有很好的判识.海螺沟冰川退缩时间序列土壤中钙铝结合态的磷主要为原生矿物磷,随成土作用增强而减少.即时生物可利用磷从30年后迅速增加,促使了植被形成和演替.
鄂尔多斯盆地东缘煤层气甲烷碳同位素分布及成因

鄂尔多斯盆地东缘煤层气甲烷碳同位素分布及其成因对认识该区煤层气藏的形成和分布规律,煤层气资源评价具有重要意义.在系统总结该区煤层气组分和煤层气碳同位素的地域、时域和煤阶分布特征的基础上,结合煤储层演化过程,分析了甲烷碳同位素的变化规律.该区甲烷碳同位素分布范围宽,同位素组成总体偏轻,地域上由北往南呈现"变轻-加重-变轻"的趋势,针对性分析认为北部低煤阶次生生物气的生成,中部水动力活跃地区引起的水溶解分馏,南部构造演化过程中地层抬升造成的解吸分馏,以及局部岩浆运动引起的快速增温生烃分馏是造成该区甲烷碳同位素普遍偏轻的主要因素.
基于THEMIS卫星数据的等离子体层顶位置模型

利用2010~2011年的THEMIS卫星观测的卫星电位数据反演电子密度,并用来确定等离子层顶的位置,研究其与地磁指数的关系.利用观测数据得到了一个THEMIS卫星等离子体层顶位置数据库.利用该数据库建立了新的等离子体层顶位置的磁地方时经验模型,并比较了其与现有的四个等离子体层顶位置经验模型的优劣.发现新建立的等离子体层顶位置模型明显优于其余四个经验模型.在模型的三种输入参数中,Kp指数和Dst指数模型的预测效果相当,并明显优于AE指数的模型,这说明磁层的大尺度对流强度是影响等离子体层顶位置最主要的因素.