地质论评2018第64卷第2期中英文目次、编委、封底     

章雨旭 《地质论评》2018,64(2):64029999-64029999

contents,committee,backcover  相似文献   

含盐量对水泥土强度影响的室内试验研究   总被引：1，自引：0，他引：1  

储诚富  刘松玉  邓永锋  邵俐 《工程地质学报》2007,15(1):139-143

通过含盐量对非有机质土加固强度影响的试验研究,得到了含盐量对水泥土强度的提高或减小的阈值为3.5%。当盐渍土的含盐量低于这个阈值时,盐渍土的加固强度会因可溶性盐的结晶膨胀作用,提高水泥土的强度;相反当盐渍土的含盐量高于该阈值时,盐渍土的强度会因可溶性盐的过多的结晶膨胀作用,使水泥土的结构遭到破坏,从而使水泥土的强度大大降低。同时分析了可溶性硫酸盐、镁盐和氯盐对水泥土的浸蚀性作用,并从盐类对水泥土强度的影响从机理上进行了阐释,提出了高含盐量对水泥土破坏作用的对策。  相似文献   

海洋沉积物黏土矿物相对含量不同计算方法对比研究     

舒雨婷  刘志杰  余佳  孔敏  田先德  刘升发 《海洋通报》2019,(5):585-590

海洋沉积物黏土矿物相对含量计算存在多种计算方法,并不统一,限制了异源黏土矿物的整合和使用。文章选取了两种较为常见的计算方法,即Biscaye和国标中规定的计算方法,分别对东印度洋109个表层样品黏土矿物的相对百分含量进行计算,分析对比了两种方法计算结果之间的差异。结果显示,两种计算方法结果存在显著正相关,都能显示黏土矿物分布的变化趋势,4种黏土矿物相关系数由高到底分别为:蒙皂石0.986、伊利石0.974、绿泥石0.924、高岭石0.923。相对于Biscaye计算方法,国标计算方法会增加伊利石和高岭石的相对百分含量而降低蒙皂石和绿泥石的相对百分含量。两种计算方法黏土矿物的含量相关性较好,可以建立起相互数学转换关系式。但在不同的海区,由于矿物成因、结晶程度以及混层矿物的出现可能会使衍射峰形态发生改变,从而相关性系数和转换关系也会相应发生改变。  相似文献   

Sharks caught in the KwaZulu-Natal bather protection programme,South Africa. 14. The smooth hammerhead shark Sphyrna zygaena (Linnaeus)     

ML Dicken  H Winker  MJ Smale  G Cliff 《African Journal of Marine Science》2018,40(2):157-174

The current study provides long-term catch-rate, biological and feeding data for smooth hammerhead sharks, Sphyrna zygaena, caught in South Africa’s KwaZulu-Natal bather protection programme. In total, 2 512 S. zygaena were caught in net installations between 1978 and 2014, and 72 S. zygaena were caught on drumlines between 2007 and 2014. There was no significant log-linear year trend in the net catch rate over time (slope = 0.0054, t = 1.808, p = 0.07). However, there was a significant temporal increase in mean size of the captured sharks (slope = 0.0012, t = 3.502, p < 0.001). A quasi-Poisson generalised additive mixed model showed that increasing latitude, winter months, colder sea temperatures and the deployment of drumlines all had a significant positive effect on the catch rate of sharks in nets. The size frequency of the catch was unimodal, with significantly more females caught in the nets and more males on the drumlines. The majority (93.1%) of all sharks caught were immature and measured between 80 and 120 cm precaudal length. Teleosts and cephalopods dominated the sharks’ diet in terms of all dietary indices. The prey species consumed indicate that immature S. zygaena are feeding primarily within the pelagic zone of shallow coastal habitats.  相似文献   

腾格里沙漠东南缘人工固沙植被区表层土壤有机碳矿化对凋落物添加的响应   总被引：2，自引：2，他引：0  

李云飞  谢婷  石万里  李小军 《中国沙漠》2019,39(5):200-209

土壤有机碳矿化是调控土壤碳库时空格局、土壤碳收支平衡和植物养分供应的重要过程,植物残体和凋落物分解释放CO₂直接影响着土壤有机碳矿化。研究了不同类型凋落物对腾格里沙漠东南缘建植于1956年的人工固沙植被区土壤有机碳矿化过程及其对水分和温度的响应特征。结果表明：凋落物添加显著促进了有机碳矿化,添加柠条锦鸡儿（Caragana korshinskii）、油蒿（Artemisia ordosica）、小画眉草（Eragrostis minor）凋落物后,CO₂-C最大矿化速率分别增大了6.94、5.17、3.46倍,0~5 cm层土壤是5~10 cm层土壤的1.09、1.55、1.22倍;CO₂-C累积释放量分别增加了3.73、3.38、2.34倍,0~5 cm层土壤是5~10 cm层土壤的1.17、1.30、1.57倍。凋落物对有机碳矿化的促进作用与温度和水分密切相关,25℃时,CO₂-C平均释放速率、最大释放速率、累积碳释放量分别是10℃的2.21、3.60、2.21倍,而含水量10%时,CO₂-C平均释放速率、最大释放速率和累积碳释放量分别是含水量5%时的1.25、1.20、1.25倍。相关性分析表明,凋落物碳氮含量、碳氮比、木质素比氮和土壤有机碳以及全氮是影响有机碳矿化的主要因子。凋落添加土壤后潜在可矿化碳表现为柠条锦鸡儿>油蒿>小画眉草>对照。凋落物添加显著促进了有机碳矿化过程及碳周转,植被恢复过程中草本植物凋落物的输入更有利于土壤碳固存,凋落物对土壤碳库的调控作用受土壤理化性质和水热等环境因子的共同作用影响。  相似文献   

The protoliths to the sillimanite gneisses from the Larsemann Hills and geological implication in their formation     

任留东  杨崇辉  王彦斌  刘平  赵越 《极地研究(英文版)》2009,20(1):1-14

The source rock from which the sillimanite gneisses derive mainly was the biotite plagioclase gneiss in the Larsemann Hills. It is the deformation-metamorphism process under special pressure and temperature condition, not the original rock compositions, that controls the presence of sillimanite. To a great degree, the sillimanite gneiss was the mixture of the detaining materials of the migrating felsic melt from the bt-plagioclase gneiss that underwent partial melting and the relics when the melt was removed. In sillimanitization the original rock had been changed substantially in chemical composition. The related metamorphism process severely deviated from the isochemical series, the process was of, therefore, an open system. In addition, the Al2O3 contents of the original rock was an important, but not critical factor for the formation of sillimanite, i.e., the sillimanite-bearing rock need not be of aluminum rich in composition, and vise contrarily, the aluminum rock may not produce sillimanite. The authors of the present paper postulate that the source rock from which the aluminum rich rock derives need not be of aluminum rich, but sillimanitization is generally the Al2O3 increasing process. The aluminum rich sediments such as clay or shale need not correspond directly to sillimanite-rich gneisses. No argillaceous rock present equals to sillimanite-rich gneiss in chemical composition. The protoliths to the sillimanite gneisses from the Larsemann Hills, east Antarctica, and their adjacent area may be pelite, shale greywacke, sub-greywacke, quartz sandstone and quartz-tourmalinite. If correct, the conclusion will be of significant implication for the determination of the sillimanite gneiss formation process and the reconstruction of the protolith setting.  相似文献   

An Examination of Behavior and Hazards Faced by Physically Disabled People During the Loma Prieta Earthquake     

Mansour Rahimi 《Natural Hazards》1993,7(1):59-82

There is a need to study hazards faced by physically disabled people during earthquakes. A literature review showed the importance of occupant behavior as a factor that contributes to casualty during earthquakes. A survey questionnaire was used to study the behavioral responses of 33 disabled residents, none of whom sustained injury, during the Loma Prieta earthquake of 17 October 1989. An occupant risk analysis methodology was developed to study the sequence of activities of the disabled people. Severe restrictions in the physical capabilities of the respondents did not appear to increase their exposure to hazards. Overall, the physically disabled occupants did not think of themselves as vulnerable, and those who felt vulnerable initiated self-protective action in response to the hazards present in their immediate surroundings.  相似文献   

Diel changes in the feeding behaviour of Arctic char (Salvelinus alpinus) and brown trout (Salmo trutta) in Ellidavatn, a small lake in southwest Iceland     

Bjrn Bjrnsson 《Limnologica》2001,31(4):281-288

In the lake Ellidavatn, southwest Iceland, the diel activity of Arctic char and brown trout was studied in autumn (September) and spring (April) by removing the fish from gillnets every 3 hours for three days. Additional fish samples, evening and morning, were taken at other times of the year. The catch per unit effort was about 10 times higher during the nighttime than daytime for both char and trout. The median weight of char was lowest near the middle of night (80 g) and highest near the middle of day (140 g). The median weight of trout was also lowest near the middle of night (110 g) and highest near the middle of day (330 g). The main diet of char consisted of the cladoceran Eurycercus lamellatus in September and chironomid larvae in April and the main diet of trout was always sticklebacks. In autumn and spring, the feeding was nocturnal in the char but crepuscular in the trout. The median stomach content of char was highest at dawn (0.52% of body weight) and lowest at dusk (0.14% of body weight). It is proposed that nocturnal char shift through the bottom substrate in search for prey. The median stomach content of trout was highest at 09.00–18.00 and 24.00–03.00 hours (0.13–0.18% of body weight) and lowest at 03.00–06.00 and 18.00–21.00 hours (0.02–0.07% of body weight). Different feeding times may help to secure mutual coexistence of char and trout in a small lake. In autumn and spring, the average daily consumption of char was about 0.8% of body weight, less than half their maximum food intake.  相似文献   

山地学的研究对象和内容浅议──续《发展山地学之我见》     

余大富 《山地学报》1998,(1)

建议将山地学的研究对象定为以地域自然-人文综合体存在的山地系统即山地人地系统．据此提出了山地学的研究内容应围绕山地系统的性质、结构、功能及其演变理论和研究方法这一中心论题展开．  相似文献   

加味归芍异功散联合西药四联疗法治疗幽门螺杆菌相关性慢性胃炎30例          下载免费PDF全文

张件云  贺莉娟  尹萍 《应用海洋学学报》2022,38(12):13

目的：观察加味归芍异功散合西药四联疗法治疗脾胃虚弱型幽门螺杆菌（Hp）相关性慢性胃炎的临床疗效。方法：将60 例Hp相关性慢性胃炎脾胃虚弱证患者按照随机数字表法分为治疗组和对照组,每组各30 例。治疗组采用加味归芍异功散合西药四联疗法治疗,对照组仅采用西药四联疗法治疗,比较2组的中医证候疗效、Hp根除情况、中医证候评分（胃脘隐痛、胃脘胀满、乏力、纳呆、气短、大便稀溏）以及不良反应发生情况。结果：中医证候疗效总有效率治疗组为100.00%（30/30）,对照组为93.34%（28/30）,2组比较,差异有统计学意义（P<0.01）;Hp根除总有效率治疗组为100.00%（30/30）,对照组为80.00%（24/30）,2组比较,差异有统计学意义（P<0.05）;2组治疗后中医证候各项评分均较治疗前下降,且治疗组下降幅度较对照组更大（P<0.05）;不良反应发生率治疗组为6.67%（2/30）,对照组为20.00%（6/30）,组间比较,差异无统计学意义（P>0.05）。结论：加味归芍异功散合西药四联疗法治疗Hp相关性慢性胃炎脾胃虚弱证的临床疗效优于单用四联疗法,值得临床推广应用。  相似文献