Study on the model for predicting soil erosion and its application in arid area

１　ＴＨＥＡＮＡＬＹＳＩＳＯＦＳＯＩＬＥＲＯＳＩＯＮＦＡＣＴＯＲＳＴｈｅｉｎｔｅｎｓｉｔｙｏｆｓｏｉｌｅｒｏｓｉｏｎｉｎａｒｉｄａｒｅａｖａｒｉｅｓｗｉｔｈａｌｔｉｔｕｄｅ,ｍｏｉｓｔｕｒｅａｎｄｈｅａｔｃｏｎｄｉｔｉｏｎａｎｄｓｕｒｆａｃｅｌａｙｅｒ（Ｃｈｅｎ,１９９５）．Ｉｎｍｉｄｄｌｅａｎｄｈｉｇｈｍｏｕｎｔａｉｎｓｅｃｔｉｏｎｓ,ｔｈｅｒｅｉｓａｌｉｔｔｌｅｍｏｒｅｐｒｅｃｉｐｉｔａｔｉｏｎ（４５０－７９６．９０ｍｍ）,ｒｉｃｈｅｒｖｅｇｅｔａｔｉｏｎｃｏｖｅｒｍｏｒｅｔｈａｎ６０ｐｅ…     

Influence of principal stress rotation of unequal tensile and compressive stress amplitudes on characteristics of soft clay

Soil behavior can reflect the characteristics of principal stress rotation under dynamic wave and traffic loads. Unequal amplitudes of tensile and compressive stresses applied to soils have complex effects on foundation soils in comparison with the pure principal stress rotation path. A series of undrained cyclic hollow torsional shear tests were performed on typical remolded soft clay from the Hexi area of Nanjing, China. The main control parameters were the tensile and compressive stress amplitude ratio(α) and the cyclic dynamic stress ratio(η). It was found that the critical η tended to remain constant at 0.13, when the value of the compressive stress amplitude was higher than the tensile stress amplitude. However, the influence of the tensile stress was limited by the dynamic stress level when α= 1.For obvious structural change in the soil, the corresponding numbers of cyclic vibration cycles were found to be independent of α at low stress levels and were only related to η. Finally, a new method for evaluating the failure of remolded soft clay was presented. It considers the influence of the tensile and compressive stresses which caused by complex stress paths of the principal stress rotation. This criterion can distinguish stable, critical, and destructive states based on the pore-water-pressure-strain coupling curve while also providing a range of failure strain and vibration cycles. These results provide the theoretical support for systematic studies of principal stress rotation using constitutive models.     

富水断层非标准三角堰测法流量计算方法及工程应用

公路、铁路、水利水电、矿山等隧道工程建设和运营过程中,不可避免地会遭遇塌方、突涌水等地质灾害问题,围岩失稳破坏和渗流突变是发生突水的直接原因。为查明龙南隧道F₈富水断层洞身范围涌水来源及其涌水量的大小,采用非标准三角堰测法结合矩形堰测法现场监测F₈断层地表上、下游流量。本研究提出非标准三角堰测法的基本概念,并根据标准三角堰测法流量公式,结合流量的等效原理,推导出了非标准三角堰测法流量公式。通过理论与实测数据进行比较,证明了本公式的合理性。研究结果表明,非标准三角堰测法流量公式的推导为现场流量实测提供了方便,克服了标准三角堰测法公式适用范围不足的缺点,为分析断层破碎带洞身围岩范围内涌水量大小提供了可靠依据。      

THE METHOD BASE OF GEOGRAPHIC ANALYSIS AND ITS APPLICATION

曹桂发ＴＨＥＭＥＴＨＯＤＢＡＳＥＯＦＧＥＯＧＲＡＰＨＩＣＡＮＡＬＹＳＩＳＡＮＤＩＴＳＡＰＰＬＩＣＡＴＩＯＮ￥ＣａｏＧｕｉｆａ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒｙｏｆＲｅｓｏｕｒｃｅｓａｎｄＥｎｖｉｒｏｎｍｅｎｔａｌｉｎｆｏｒｍａｔｉｏｎＳｙｓｔｅｍ...     

A numerical method of combined SPF-MEM-LBM on the rockfall-induced surge and its application

Rockfalls in reservoirs are prone to induce surges,posing a severe threat to passing vessels and facilities.A scheme combined Single-phase free-surface method (...     

基于“三段法”的锚拉桩桩身内力计算方法与应用

针对抗滑桩常因地质条件、地形地貌等原因导致受荷段底面与嵌固段顶面不在同一水平面的情况,将此段划为次受荷段,并推导了次受荷段桩后设计荷载大小计算公式和荷载分布公式,以及在弹性地基梁和悬臂梁模型下的适用于悬臂桩和锚索桩内力与挠度计算通用公式。以巴东县焦家湾移民安置点库岸防护工程预应力锚索桩为例,研究次受荷段对抗滑桩内力和挠度影响。结果表明:忽略次受荷段后土压力作用的传统计算方法会使桩身弯矩计算结果偏小,导致桩身配筋量不足,存在设计安全隐患。再以锚索排数、位置为控制变量,研究其对预应力锚索桩内力和挠度的影响,提出预应力锚索可有效地降低抗滑桩工程造价;增加预应力锚索的排数有利于调节抗滑桩内力分布,设计时应优先考虑将锚索设置为多排锚索。      

A FINITE ELEMENT METHOD FOR COMPUTATIONAL FLUID DYNAMICS WITH APPLICATION TO TIDAL CALCULATION OF THE BOHAI SEA

The finite element method is art established numerical technique which now enjoys a widespread use in solid and structural mechanics. The main attributes are its fairly wide flexibility in handling very complex geometrics, its rich mathematical structure in developing efficient and accurate elements and its advantages of having to satisfy only the essential boundary conditions. It is effective, especially in the case where the domain is not regular.     

Property and performance amelioration of pelagic clay from the East Pacific

To make use of the pelagic clay as polymer filling, the properties of clay sediments from the ocean investigation zone of China in the East Pacific were studied by the SSA, XRF, ICP/MAS, FTIR, XRD, SEM, DTA/TG and granularity distributing etc. , and experiments were settled to improve the whiteness and activation of the clay based on these data. Compared with land clay, pelagic clay holds many particular features, such as fine particles and incompact accumulation, worse crystallization and more defects, high activity, complex mineral and chemical components, and low whiteness etc. Processing the purified pelagic clay with acids and zinc, then baked it at different temperatures, the whiteness of clay can be increased from 23.8% to 73.1%, and the optimized conditions is： consistency of vitriol 25%, ratio of clay to water 4： 1, reaction time 4h, reaction temperature 90℃, dosage of zinc 2.0 g/L, and baking temperature 700℃. And the SSA of whited clay is increased too. Using the dry milling method to modify the pelagic clay with organic reagents, the optimized technique is KH550, concentration 1.5%, reaction time 20 min. XRD, FTIR and SEM testing indicate that the mechanism of organic activation was mainly surface absorbing and chemical combination secondly.     

一种AJAX Web应用程序自动化测试方法的研究与设计

针对传统自动化测试方法的缺陷,基于AJAX关键技术和异步工作模式,分析及设计了一种适合于AJAX Web应用程序的异步自动化测试方法.重点介绍了此异步自动化测试技术的框架构建以及一对核心程序定义函数:access和wait的设计实现.     

Properties and organic activation of ocean clay in the East Pacific

In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5% (volume) of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly.     

Red Clay Sediment in the Central Chinese Loess Plateau and Its Implication for the Uplift of the Tibetan Plateau

Introduction A set of reddish clay-silt-sized sediments named red clay underlying the Quaternary loess-paleosol sequence widely distribute in the Chinese Loess Plateau. The thickness of the red clay sediments ranges from decades of meters to over 100 m (Evan et al.1991,Mo and Derbyshire 1991, SUN et al. 1997&1998, DING et al. 1999, GUO et al. 2001, QIANG et al. 2001). Previous studies show that not only loess-paleosol (e.g.LIU et al.1985,AN et al.1990,DING et al.1992),but also red …     

Properties and organic activation of ocean clay in the East Pacific

In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5 % （volume） of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly.     

Property and performance amelioration of pelagic clay from the East Pacific

To make use of the pelagic clay as polymer filling, the properties of clay sediments from the ocean investigation zone of China in the East Pacific were studied by the SSA, XRF, ICP/MAS, FHR, XRD, SEM, DTA/TG and granularity distributing etc. , and experiments were settled to improve the whiteness and activation of the clay based on these data. Compared with land clay, pelagic clay holds many particular features, such as fine particles and incompact accumulation, worse crystallization and more defects, high activity, complex mineral and chemical components, and low whiteness etc. Processing the purified pelagic clay with acids and zinc, then baked it at different temperatures, the whiteness of clay can be increased from 23.8% to 73.1%, and the optimized conditions is : consistency of vitriol 25%, ratio of clay to water 4:1, reaction time 4h, reaction temperature 90℃, dosage of zinc 2.0 g/L, and baking temperature 700℃. And the SSA of whited clay is increased too. Using the dry milling method to modify the pelagic clay with organic reagents, the optimized technique is KH550, concentration 1.5%, reaction time 20 min. XRD,FTIR and SEM testing indicate that the mechanism of organic activation was mainly surface absorbing and chemical combination secondly.     

NEW METHOD TO OBTAIN THE POWER SPECTRA OF HIDDEN VARIABLES AND ITS APPLICATION TO OCEAN DATA

A novel method is proposed to obtain the power spectra of hidden variables in a chaotic time series. By embedding the data in phase space , and recording the conditional probability densityof points that the trajectory encounters as it evolves in the reconstructed phase space, it is possible torecover the power spectra of hidden variables in chaotic time series through a spectral analysis over theconditional probability density time series. The method is robust in the application to Lorenz system, 4-di-mension Rossler system and rigid body motion by linear feedback system (LFRBM). Applying the method the time series of sea surface temperature (SST) of the South China Sea, we obtained the power spectraof the wind speed (WS) from SST data. Furthermore, the results showged that there exists an importantnonlinear interaction between the SST and the WS.     

Improved AHP method and its application in lake environmental comprehensive quality evaluation a case study of Xuanwu Lake, Nanjing, China

The relative importance of each pollution factor in analytical hierarchy process (AHP) method comes from pooling expert opinions in general. Because expert opinions are based on information and judgment criteria, determining their weight may lead to uncertainty.. Therefore, an improved AHP method had been developed. The process of the improved AHP method involved four key procedures. The weights of pollution factors were completely related to the objective monitoring data through the standardization of these procedures. The environmental comprehensive quality of water and sediment of Xuanwu Lake, Nanjing, China had been evaluated. The environmental quality comprehensive indices (EQCI) of the water in 1991-1995 and 1996-2000 were 3.32 and 1.85, respectively, indicating that the water quality improved. The EQCI of the sediment in 1995 and 2000 indicates that the sediment contamination decreased from 1995 to 2000. Such results agreed with the fact that the lake had been under comprehensive control. However, with the classical AHP method, the EQCI of the sediment in the northwestern part of the lake may have indicated that sediment contamination increased from 1995 to 2000. The discrepancy may have resulted from the judgment difference of the experts. The improved AHP method can avoid arbitrariness of subjective judgment and can reflect the real influential factors of environment pollution in different periods or regions.     

Extraction method of component waves in full waveform acoustic data and its application

In conventional slowness-time coherence(STC)method,slowness and time need to be searched at the same time,which limits the precision and lowers the efficiency.The dichotomy method combined with slowness-time coherence algorithm aims to enhance the efficiency of data processing and to improve the precision.The algorithm changes the searching pattern of conventional slowness-time coherence method to acquire the slowness of component waves in array acoustic logging data.Based on energy ratio of short time window versus long time window and slowness-time coherence method,the algorithm first acquires the arrivals of the component waves using energy ratio of short time window versus long time window method.It then uses the calculated results as the arrivals in conventional slowness-time coherence method,so the slowness-time two-dimensional searching process is simplified to slowness searching process.Based on dichotomy method,the searching pattern is further optimized in replace of the ergodic searching pattern in conventional slowness-time coherence method,which means that as the iteration proceeds,the current searching interval is reduced to half of the former,so the number of searching times is decreased.The dichotomy method combined with slowness-time coherence algorithm is applied to well L in the data processing.Compared with conventional slowness-time coherence method,for compressional wave,the searching efficiency of the algorithm is 4.53 times better,while for Stoneley wave,the searching efficiency is 1.85 times better.Compared with conventional logging data,the average absolute error of the results of the dichotomy method combined with slowness-time coherence algorithm is 1.14μs/ft smaller than that of the conventional method,while the average relative error is 1.2 percent lower.The dichotomy method combined with slowness-time coherence algorithm shows good results in its application,which can enhance the processing efficiency remarkably while getting reliable results at the same time.     

实现砖瓦窑业管理秩序的长治久安--扬州市开展砖瓦窑业专项治理整顿的实践

扬州市抓住省斤以高邮为试点的契机．在全市范围内开展了砖瓦窑业专项治理整顿工作。由于政府重视、责任明确、组织到位、措施有力．全市共关停、炸毁各类窑厂1443座．复垦土地701.2hm^2，整治工作取得了阶段性成果。在专项整治过程中，着力强化基层管理人员和砖瓦窑业主保护耕地，保护资源等四点意识，认真落实四个到位，努力做到了四项结合。     

纤维强制裂缝转向规律实验及现场试验

可降解纤维可以强制人工裂缝发生转向,促进复杂缝网的形成,目前还不清楚纤维强制裂缝转向规律。通过纤维滤失暂堵能力实验,评价纤维转向剂对人工裂缝的暂堵转向作用,分析纤维转向剂对不同裂缝宽度、不同流速时裂缝暂堵规律,确定形成暂堵的临界纤维质量分数。根据降解性能评价实验,纤维在少量水存在的情况下降解率能够达到85%以上,并在暂堵后依靠储层温度恢复而实现自动降解;根据真三轴压裂物模实验,验证纤维转向剂在裂缝存在条件下形成暂堵强制裂缝转向的可靠性,得出裂缝发生转向的水平主应力差上限为7.5 MPa,两次压裂产生裂缝间夹角与水平主应力差呈负相关关系。85口井次的现场纤维转向酸压工艺试验表明,转向压力最高达到40.0 MPa,增产效果明显。该研究结果对理解纤维暂堵裂缝转向机理与指导现场压裂施工设计具有指导意义。     

改革成教课程体系,培养技能型实用人才——以数控技术教育为例浅谈成教课程体系的改革

数控技术的广泛应用使制造业发生了根本性的变革。我国要成为“世界工厂” ,需要培养数十万数控技术应用领域的操作人员、编程人员和维修人员。目前 ,在经济发达的珠三角地区的各类企业中 ,已普遍使用数控设备进行生产 ,而数控方面的技术人才却极其缺乏。因此 ,为社会培养大批能熟练掌握数控技术的技能型人才 ,已成为广东省有关高校所面临的紧迫任务。以数控技术教育为切入点 ,结合我校成人教育机电专科数控专业的教学改革 ,提出了培养技能型实用人才的课程体系和人才培养模式。     

ELECTROCHEMICAL CORROSION BEHAVIOR OF STEEL IN THE JUNCTURE AREA OF SEA CLAY AND SAND

Corrosion behavior of steel in the juncture area of sea clay and sand was studied. The results show that galvanic corrosion occurred between steel samples buried in sea clay and sand, and that the polarity of the galvanic cell reversed after some testing later. The cause of reversing of polarity is discussed.