Measuring Receptor/Ligand Interaction at the Single-Bond Level: Experimental and Interpretative Issues

There is increased interest in measuring kinetic rates, lifetimes, and rupture forces of single receptor/ligand bonds. Valuable insights have been obtained from previous experiments attempting such measurements. However, it remains difficult to know with sufficient certainty that single bonds were indeed measured. Using exemplifying data, evidence supporting single-bond observation is examined and caveats in the experimental design and data interpretation are identified. Critical issues preventing definitive proof and disproof of single-bond observation include complex binding schemes, multimeric interactions, clustering, and heterogeneous surfaces. It is concluded that no single criterion is sufficient to ensure that single bonds are actually observed. However, a cumulative body of evidence may provide reasonable confidence. 0 2002 Biomedical Engineering Society.

Species transformation of trace elements and their distribution prediction in dyestuff residue incineration

The release of heavy metals from the combustion of hazardous wastes is an environmental issue of increasing concern. The species transformation characteristics of toxic heavy metals and their distribution are considered to be a complex problem of mechanism. The behavior of hazardous dyestuff residue is investigated in a tubular furnace under the general condition of hazardous waste pyrolysis and gasfication. Data interpretation has been aided by parallel theoretical study based on a thermodynamic equilibrium model based on the principle of Gibbs free energy minimization. The results show that Ni, Zn, Mn, and Cr are more enriched in dyestuff residue incineration than other heavy metals (Hg, As, and Se) subjected to volatilization. The thermodynamic model calculation is used for explaining the experiment data at 800 degrees C and analyzing species transformation of heavy metals. These results of species transformation are used to predict the distribution and emission characteristics of trace elements. Although most trace element predictions are validated by the measurements, cautions are in order due to the complexity of incineration systems.

Separation of enantiomers of drugs by capillary electrophoresis with permethyl-gamma-cyclodextrin as chiral solvating agent

High-throughput screening is a promising new approach in analytical chemistry. Within the framework of an extended screening program (The German-Chinese Drug Screening Program), the enantioseparation of 86 drugs was investigated by capillary zone electrophoresis in the presence of the chiral solvating agent (CSA) octakis-(2,3,6-tri-O-methyl)-gamma-cyclodextrin (TM-gamma-CD). By this means, 15 drugs could be separated into enantiomeric pairs. Approximate measures for the degree of interaction (migration retardation factor, R-m) and for the degree of enantiomer recognition (migration separation factors, alpha(m)) revealed intriguing patterns that were compared with those found for native gamma-cyclodextrin (gamma-CD). Although there is a distinct influence of the analyte structure on the electrophoretic data, interpretation remains difficult. Most remarkably, permethylation of gamma-CD leads neither to a higher affinity nor to better chiral recognition, in contrast to the findings with alpha-CD.

Aglacins I-K, three highly methoxylated lignans from Aglaia cordata

Further chemical investigation of the stem bark of Aglaia cordata has led to the isolation and identification of three new lignans, namely, aglacins I-K (1-3), all of which contain two contiguous trimethoxylated phenyl systems. Among them, aglacins I and J (1 and 2) are new members of the aryltetralin cyclic lactol class, while aglacin K (3) is a new example of tetralrydrofuran lignan. The structures of these compounds were established on the basis of spectroscopic data interpretation.

南堡油田测试资料综合评价及试油配套工艺技术研究与应用

A series of significant oil-gas exploration progresses have been achieved in Nanpu depression with 1.02 billion ton oil-gas reserves have been proven. It has been confirmed that Nanpu beach has a geologic condition to be a major field based on exhaustive research. This finding, which is integrated reservoir，great reserves, thick oil layer and high productivity in Nanpu depression, is the most excited success in Chinese oil-gas exploration in recent years. This abundant oilfield found is significant to the strategy of oil production stability in the east of China. Nanpu depression exploration is also a crucial exploration project for Petrochina. Based on the comprehensive research on Nanpu formation testing data, we reevaluate and analyze the reservoir property and the structure characteristics, and propose a series of testing technique that are suitable for Jidong oil field development. The results are summarized as follows: 1. The reservoir parameters and characters are defined by formation test data interpretation and systemic dynamic-static data comparison. 2. Based on sources analysis and statistical research related to formation contaminants, some technique measures, which can not only prevent or reduce invasion damage for different formations but also can effectively improve completion efficiency, are proposed. 3. By selecting the testing pressure drawdown, optimum working regulation and flow /shut-in duration, and adopting dynamic-static flow parameters correlation analysis to predict production, an optimum research on working regulation and flow /shut-in duration was accomplished. Optimization formation test principles suitable for any kinds of Nanpu oilfield are established, which can improve test quality, construction efficiency and data recording quality. 4. By reasonable selection of perforating gun and penetrating charge, the perforation penetration has been improved effectively and the flow channel of the oil gas have been expanded, so that the communication between formations and the wellbore is improved better. 5. One joint working procedure which combining formation test, perforation, unloading and stimulation treatment has become the dominant testing technology in the Nanpu offshore Oilfield. This combination technique can implement several procedures using one pipe string, and achieve rapid testing purpose.

煤系地层三维三分量地震数据解释方法研究

Conventional 3D seismic exploration cannot meet the demand of high yield and high efficiency safe production in coal mine any more. Now it is urgent to improve the discovery degree of coal mine geological structures for coal production in China. Based on 3D3C seismic exploration data, multi-component seismic information is fully excavated. First systematic research on 3D3C seismic data interpretation of coal measure strata is carried out. Firstly, by analyzing the coal measure strata, the seismic-geologic model of coal measure strata is built. Shear wave logging is built by using regression analysis. Horizon calibration methods of PP-wave and PS-wave are studied and the multi-wave data are used together to interpret small faults. Using main amplitude analysis technology, small faults which cannot be found from PP-wave sections can be interpreted from the low frequency PS-wave sections. Thus, the purpose to applying PS-wave data to fine structure assistant interpretation is achieved. Secondly, PP- and PS-wave post-stack well constrained inversion methods of coal measure strata are studied. Joint PP- and PS-wave post-stack inversion flow is established. More attribute parameters, which are applied in fine lithology interpretation of coal measure strata, are obtained from combinations of the inversion results. Exploring the relation between rock with negative Poisson’s ratio and anisotropy, fracture development in coal seam are predicted. Petrophysical features of coal measure strata are studied, and the relations between elastic parameters and lithology, fluid and physical properties are established. Inversions of the physical parameters such as porosity, permeability and water saturation, which reflect lithology and fluid property, are obtained. Finally, the approaches of shear wave splitting and Thomsen parameters inversion, which provide new ideas for seismic anisotropy interpretation of coal measure strata, are studied to predict fracture development. The results of practical application indicate that the methods in this paper have good feasibility and applicability. They have positive significance for high yield and high efficiency safe production in coal mine.

隐伏金矿床预测中的地震勘探险方法

Based on brief introduction of seismic exploration and it's general developing situation, the seismic exploration method in field work implementation and some problems frequently encountered in field, which should be pay attention to, are analyzed in detail. The most economic field work techniques are emphasized. Then the seismic data processing flow and it's interpretation technique about the processing results are presented. At last four examples of seismic prospecting in gold deposits are showed. The main conclusions of our research are: 1. Seismic prospecting technique is a very efficient method in the prediction of concealed gold deposits. With appropriate application, it can absolutely reflect the detail underground geological structure in the condition of rugged area and complicated geological environment. 2. The field geometry should be designed and changed according to different kinds of objective exploration depth and ground situation. The best field implementing parameters which include offset, the distance between two adjacent traces, the quantity of dynamite and the depth of hole for explosion, should be determined with examination. Only this way, the high quality original seismic data can be gotten. 3. In seismic data processing, the edition of invalid trace and source gather, signal enhancement, velocity analysis and migration are the key steps. It has some different points with conventional processing and needs a new processing flow and methods which is suitable to the data acquired in rugged area and complicated geological environment. 4. The new common reflection area stacking method in crooked line data processing is an efficient method to improve the signal to noise ratio of seismic data The innovations of our research work are: 1. In the areas which were considered to be forbidden zone, we implement the seismic exploration in several gold deposits in China through our application. All acquire distinguished effects. This show the seismic exploration method is a new effective method in the prediction of concealed gold deposits. 2. We developed a set of seismic field work techniques and data processing which is suitable to complex environment, especially find a effective method in stacking and noise elimination in crooked line data processing. 3. In the field of seismic profile interpretation, through our research work, we are convinced of that: in different kinds of geological condition, the seismic reflection character are not same. For example the lava, the intrusion rock and sediment layers are different in the character of reflection structure and strength. So we accumulate some experience about seismic data interpretation in the area of gold deposits.

井间地震技术研究和应用

Cross well seismic technique is a new type of geophysical method, which observes the seismic wave of the geologic body by placing both the source and receiver in the wells. By applying this method, it averted the absorption to high-frequency component of seismic signal caused by low weathering layers, thus, an extremely high-resolution seismic signal can be acquired. And extremely fine image of cross well formations, structure, and reservoir can be achieved as well. An integrated research is conducted to the high-frequency S-wave and P-wave data and some other data to determine the small faults, small structure and resolving the issues concerning the thin bed and reservoir's connectivity, fluid distribution, steam injection and fracture. This method connects the high-resolution surface seismic, logging and reservoir engineering. In this paper, based on the E & P situation in the oilfield and the theory of geophysical exploration, a research is conducted on cross well seismic technology in general and its important issues in cross well seismic technology in particular. A technological series of integrated field acquisition, data processing and interpretation and its integrated application research were developed and this new method can be applied to oilfield development and optimizing oilfield development scheme. The contents and results in this paper are as listed follows: An overview was given on the status quo and development of the cross well seismic method and problems concerning the cross well seismic technology and the difference in cross well seismic technology between China and international levels; And an analysis and comparison are given on foreign-made field data acquisition systems for cross-well seismic and pointed out the pros and cons of the field systems manufactured by these two foreign companies and this is highly valuable to import foreign-made cross well seismic field acquisition system for China. After analyses were conducted to the geometry design and field data for the cross well seismic method, a common wave field time-depth curve equation was derived and three types of pipe waves were discovered for the first time. Then, a research was conducted on the mechanism for its generation. Based on the wave field separation theory for cross well seismic method, we believe that different type of wave fields in different gather domain has different attributes characteristics, multiple methods (for instance, F-K filtering and median filtering) were applied in eliminating and suppressing the cross well disturbances and successfully separated the upgoing and downgoing waves and a satisfactory result has been achieved. In the area of wave field numerical simulation for cross well seismic method, a analysis was conducted on conventional ray tracing method and its shortcomings and proposed a minimum travel time ray tracing method based on Feraiat theory in this paper. This method is not only has high-speed calculation, but also with no rays enter into "dead end" or "blinded spot" after numerous iterations and it is become more adequate for complex velocity model. This is first time that the travel time interpolation has been brought into consideration, a dynamic ray tracing method with shortest possible path has been developed for the first arrivals of any complex mediums, such as transmission, diffraction and refraction, etc and eliminated the limitation for only traveling from one node to another node and increases the calculation accuracy for minimum travel time and ray tracing path and derives solution and corresponding edge conditions to the fourth-order differential sonic wave equation. The final step is to calculate cross well seismic synthetics for given source and receivers from multiple geological bodies. Thus, real cross-well seismic wave field can be recognized through scientific means and provides important foundation to guide the cross well seismic field geometry designing. A velocity tomographic inversion of the least square conjugated gradient method was developed for cross well seismic velocity tomopgraphic inversion and a modification has been made to object function of the old high frequency ray tracing method and put forward a thin bed oriented model for finite frequency velocity tomographic inversion method. As the theory model and results demonstrates that the method is simple and effective and is very important in seismic ray tomographic imaging for the complex geological body. Based on the characteristics of the cross well seismic algorithm, a processing flow for cross well seismic data processing has been built and optimized and applied to the production, a good section of velocity tomopgrphic inversion and cross well reflection imaging has been acquired. The cross well seismic data is acquired from the depth domain and how to interprets the depth domain data and retrieve the attributes is a brand new subject. After research was conducted on synthetics and trace integration from depth domain for the cross well seismic data interpretation, first of all, a research was conducted on logging constraint wave impedance of cross well seismic data and initially set up cross well seismic data interpretation flows. After it applied and interpreted to the cross well seismic data and a good geological results has been achieved in velocity tomographic inversion and reflection depth imaging and a lot of difficult problems for oilfield development has been resolved. This powerful, new method is good for oilfield development scheme optimization and increasing EOR. Based on conventional reservoir geological model building from logging data, a new method is also discussed on constraining the accuracy of reservoir geological model by applying the high resolution cross well seismic data and it has applied to Fan 124 project and a good results has been achieved which it presents a bight future for the cross well seismic technology.

大地电磁测深反演方法对比与可视化及应用研究

At first, the article has an introduction of the basic theory of magnetotelluric and the essential methods of data acquisition and preprocessing. After that, the article introduces the methods together with their predominance of computing transfering function such as the Least-square method, the Remote-Reference method and the Robust method. The article also describe the cause and influence of static shift, and has a summarize of how to correct the static shift efficiently, then emphasizes on the theories of the popular impedance tensor decomposition methods as Phase-sensitivity method, Groom and Bailey method, General tensor-analyzed method and Mohr circle-analyzed method. The kernal step of magnetotelluric data-processing is inversion, which is also an important content of the article. Firstly, the article introduces the basic theories of both the popular one-dimensional inversion methods as Automod, Occam, Rhoplus, Bostick and Ipi2win and the two-dimensional inversion methods as Occam, Rebocc, Abie and Nlcg. Then, the article is focused on parallel-analysis of the applying advantage of each inversion method with practical models, and obtains meaningful conclusion. Visual program design of magnetotelluric data-processing is another kernal part of the article. The bypast visual program design of magnetotelluric data-processing is not satisfied and systemic, for example, the data-processing method is single, the data-management is not systemic, the data format is not uniform. The article bases the visual program design of magnetotelluric data-processing upon practicability, structurality, variety and extensibility, and adopts database technology and mixed language program design method; finally, a magnetotelluric data management and processing system that integrates database saving and fetching system, data-processing system and graphical displaying system. Finally, the article comes onto the magnetotelluric application.takeing the Tulargen Cu-Ni mining area in Xingjiang as the practical example, using the data-processing methods introduced before, the article has a detailed introduction of magnetotelluric data interpretation procedure.

人工源频率域大地电磁法正反演研究

The CSAMT method is playing an important role in the exploration of geothermal and the pre-exploration in tunnel construction project recently. In order to instruct the interpretation technique for the field data, the forward method from ID to 3D and inversion method in ID and 2D are developed in this paper for the artificial source magnetotelluric in frequency domain. In general, the artificial source data are inverted only after the near field is corrected on the basis of the assumption of half-homogeneous space; however, this method is not suitable for the complex structure because the assumption is not valid any more. Recently the new idea about inversion scheme without near field correction is published in order to avoid the near field correction error. We try to discuss different inversion scheme in ID and 2D using the data without near field correction.The numerical integration method is used to do the forward modeling in ID CSAMT method o The infinite line source is used in the 2D finite-element forward modeling, where the near-field effect is occurred as in the CSAMT method because of using artificial source. The pseudo-delta function is used to modeling the source distribution, which reduces the singularity when solving the finite-element equations. The effect on the exploration area is discussed when anomalous body exists under the source or between the source and exploration area; A series of digital test show the 2D finite element method are correct, the results of modeling has important significant for CSAMT data interpretation. For 3D finite-element forward modeling, the finite-element equation is derived by Galerkin method and the divergence condition is add forcedly to the forward equation, the forward modeling result of the half homogeneous space model is correct.The new inversion idea without near field correction is followed to develop new inversion methods in ID and 2D in the paper. All of the inversion schemes use the data without near field correction, which avoid introducing errors caused by near field correction. The modified grid parameter method and the layer-by-layer inversion method are joined in the ID inversion scheme. The RRI method with artificial source are developed and finite-element inversion method are used in 2D inversion scheme. The inversion results using digital data and the field data are accordant to the model and the known geology data separately, which means the inversion without near field correction is accessible. The feasibility to invert the data only in exploration area is discussed when the anomalous body exists between the source and the exploration area.

金属矿集区深层结构高分辨率地震探测——以安徽铜陵金属矿为例

The reflection seismic prospecting technique is an important and a widely used method in the petroleum and coal surveying, and has been developed to a perfectly mature technique from the aspects of data acquisition, data processing to data interpretation. However, the metallic mine seismic prospecting, especially the high resolution seismic prospecting technique are being still in the course of studying and probing up to now. In this paper, the basic theory and the present situation of study on metallic mine seismic reflection are expatiated, the basic theory, the improving measure, the converging velocity and the ability on the integrating global optimization method are also illuminated in detail at first. Then the basic theory, the realization process and the practicing effects of the vector suppressing noise algorithm are also introduced. On the basis of studying of applying the integrating global optimization method to static correction and the vector suppressing noise algorithm, we elaborate processed the seismic data of Tongling metallic mine. We introduced the processing flow, the key steps and the processing effects. Basing on the processing results, we analyzed the major reflection characteristics, the geological interpretation results and the earth's crust top reflection structure and the space distribution status of Wutong set, the space shape of part lithological body and the contacting relations of horizonsunveiled.

2-D and 3-D processing and interpretation of multi-fold ground penetrating radar data:a case history from an archaeological site

A 2.5-D and 3-D multi-fold GPR survey was carried out in the Archaeological Park of Aquileia (northern Italy). The primary objective of the study was the identification of targets of potential archaeological interest in an area designated by local archaeological authorities. The second geophysical objective was to test 2-D and 3-D multi-fold methods and to study localised targets of unknown shape and dimensions in hostile soil conditions. Several portions of the acquisition grid were processed in common offset (CO), common shot (CSG) and common mid point (CMP) geometry. An 8×8 m area was studied with orthogonal CMPs thus achieving a 3-D subsurface coverage with azimuthal range limited to two normal components. Coherent noise components were identified in the pre-stack domain and removed by means of FK filtering of CMP records. Stack velocities were obtained from conventional velocity analysis and azimuthal velocity analysis of 3-D pre-stack gathers. Two major discontinuities were identified in the area of study. The deeper one most probably coincides with the paleosol at the base of the layer associated with activities of man in the area in the last 2500 years. This interpretation is in agreement with the results obtained from nearby cores and excavations. The shallow discontinuity is observed in a part of the investigated area and it shows local interruptions with a linear distribution on the grid. Such interruptions may correspond to buried targets of archaeological interest. The prominent enhancement of the subsurface images obtained by means of multi-fold techniques, compared with the relatively poor quality of the conventional single-fold georadar sections, indicates that multi-fold methods are well suited for the application to high resolution studies in archaeology.

YIELD BEHAVIOR AND VISCOELASTIC INTERPRETATION BY ACTIVATION VOLUMEN OF PHENOLPHTHALEIN POLYETHER KETONE

Phenolphthalein polyether ketone (PEK-C) exhibits a marked tensile yield behaviour. The yield stress depends on strain rate and the activation volume V could be evaluated from the data of the yield stress. From the creep and stress relaxation behaviour,

A quasi-synoptic interpretation of water mass distribution and circulation in the western North Pacific II: Circulation

Using the data of conductivity-temperature-depth (CTD) intensive observations conducted during Oct.-Nov. 2005, this study provides the first three-dimension quasi-synoptic description of the circulation in the western North Pacific. Several novel phenomena are revealed, especially in the deep ocean where earlier observations were very sparse. During the observations, the North Equatorial Current (NEC) splits at about 12A degrees N near the sea surface. This bifurcation shifts northward with depth, reaching about 20A degrees N at 1 000 m, and then remains nearly unchanged to as deep as 2 000 m. The Luzon Undercurrent (LUC), emerging below the Kuroshio from about 21A degrees N, intensifies southward, with its upper boundary surfacing around 12A degrees N. From there, part of the LUC separates from the coast, while the rest continues southward to join the Mindanao Current (MC). The MC extends to 2 000 m near the coast, and appears to be closely related to the subsurface cyclonic eddies which overlap low-salinity water from the North Pacific. The Mindanao Undercurrent (MUC), carrying waters from the South Pacific, shifts eastward upon approaching the Mindanao coast and eventually becomes part of the eastward undercurrent between 10A degrees N and 12A degrees N at 130A degrees E. In the upper 2 000 dbar, the total westward transport across 130A degrees E between 7.5A degrees N and 18A degrees N reaches 65.4 Sv (1 Sv = 10(-6) m(3)s(-1)), the northward transport across 18A degrees N from Luzon coast to 130A degrees E is up to 35.0 Sv, and the southward transport across 7.5A degrees N from Mindanao coast to 130A degrees E is 27.9 Sv.