Commissioning test of LAPECR2 source on the 320kV HV platform

The high charge state all permanent Electron Cyclotron Resonance Ion Source (ECRIS) LAPECR2 (Lanzhou All Permanent magnet ECR ion source No.2) has been successfully put on the 320kV HV platform at IMP and also has been connected with the successive LEBT system. This source is the largest and heaviest all permanent magnet ECRIS in the world. The maximum mirror field is 1.28T (without iron plug) and the effective plasma chamber volume is as large as circle divide 67mm x 255mm. It was designed to be operated at 14.5GHz and aimed to produce medium charge state and high charge state gaseous and also metallic ion beams. The source has already successfully delivered some intense gaseous ion beams to successive experimental terminals. This paper will give a brief overview of the basic features of this permanent magnet ECRIS. Then commissioning results of this source on the platform, the design of the extraction system together with the successive LEBT system will be presented.

Amplified electrochemical aptasensor taking AuNPs based sandwich sensing platform as a model

Here, we report a sensitive amplified electrochemical impedimetric aptasensor for thrombin, a kind of serine protease that plays important role in thrombosis and haemostasis. For improving detection sensitivity, a sandwich sensing platform is fabricated, in which the thiolated aptamers are firstly immobilized on a gold substrate to capture the thrombin molecules, and then the aptamer functionalized Au nanoparticles (AuNPs) are used to amplify the impedimetric signals.

Electrochemical Sensing and Biosensing Platform Based on Chemically Reduced Graphene Oxide

In this paper, the characterization and application of a chemically reduced graphene oxide modified glassy carbon (CR-GO/GC) electrode, a novel electrode system, for the preparation of electrochemical sensing and biosensing platform are proposed. Different kinds of important inorganic and organic electroactive compounds (i.e., probe molecule (potassium ferricyanide), free bases of DNA (guanine (G), adenine (A), thymine (T), and cytosine (C)), oxidase/dehydrogenase-related molecules (hydrogen peroxide (H2O2/beta-nicotinamide adenine dinucleotide (NADH)), neurotransmitters (dopamine (DA)), and other biological molecules (ascorbic acid (AA), uric acid (UA), and acetaminophen (APAP)) were employed to study their electrochemical responses at the CR-GO/GC electrode, which shows more favorable electron transfer kinetics than graphite modified glassy carbon (graphite/GC) and glassy carbon (GC) electrodes.

Au nanoparticles grafted sandwich platform used amplified small molecule electrochemical aptasensor

We report a sensitively amplified electrochemical aptasensor using adenosine triphosphate (ATP) as a model. ATP is a multifunctional nucleotide thatis most important as a "molecular currency" of intracellular energy transfer. In the sensing process, duplexes consisting of partly complementary strand (PCS1), ATP aptamer (ABA) and another partly complementary strand (PCS2) were immobilized onto Au electrode through the 5'-HS on the PCS1. Meanwhile, PCS2 was grafted with the Au nanoparticles (AuNPs) to amplify the detection signals. In the absence of ATP, probe methylene blue (MB) bound to the DNA duplexes and also bound to guanine bases specifically to produce a strong differential pulse voltammetry (DPV) signal. But when ATP exists, the ABA-PCS2 or ABA-PCS1 part duplexes might be destroyed, which decreased the amount of MB on the electrode and led to obviously decreased DPV signal.

Nafion-graphene nanocomposite film as enhanced sensing platform for ultrasensitive determination of cadmium

In this work, an ultrasensitive platform for the detection of cadmium (Cd2+) combining the nafion-graphene nanocomposite film with differential pulse anodic stripping voltammetry (DPASV) analysis was presented. It is found that this sensing platform exhibits enhanced response to the determination of the Cd2+ and has been used to determine the Cd2+ in real sample with good recovery.

Electrogenerated chemiluminescence sensing platform using Ru(bpy)(3)(2+) doped silica nanoparticles and carbon nanotubes

An effective electrogenerated chemiluminescence (ECL) sensor was developed by coimmobilization of the Ru(bpy)(2)(3+)-doped silica (RuDS) nanoparticles and carbon nanotubes (CNTs) on glassy carbon electrode through hydrophobic interaction. The uniform RuDS nanoparticles were prepared by a water-in-oil (W/O) microemulsion method and Ru(bpy)(3)(2+) doped inside could still maintain its high ECL efficiency. With such unique immobilization method, a great deal of Ru(bpy)(3)(2+) was immobilized three-dimensionally on the electrode , which could greatly enhance the ECL response and result in the increased sensitivity. On the other hand, CNTs played dual roles as matrix to immobilize RuDS nanoparticles and promoter to accelerate the electron transfer between Ru(bpy)(3)(2+) and the electrode. The as-prepared ECL sensor displayed good sensitivity and stability.

Instrumented impact testing of phenolphthalein polyether ketone

The Charpy impact fracture behaviour of unnotched specimens of phenolphthalein polyether ketone (PEK-C) was studied over a temperature range from room temperature to 220 degrees C by using an instrumented impact tester. The load-time and energy-time curves of PEK-C at different temperatures were recorded. From these curves, some important parameters, such as the maximum impact load, the maximum stress, the total impact energy, the crack initiation energy, the crack propagation energy etc., were obtained and their temperature dependences of PEK-C were investigated. The point of 100 percent maximum load on the load-time trace was shown to be the yield point. Two parameters, the ductile ratio (D.R.) and the ductility index (D.I.) were applied to characterize the ductility of PEK-C and their relationships to the relaxation processes were discussed.

Corrosion fatigue of welded joints of steel for marine platform

Experiments on the corrosion fatigue behaviour of welded joints of the steel for marine platform in air and seawater, and of the joints in seawater with cathodic protection, yielded data for linear regression to obtain fatigue life curves (Delta S-N-f). The laws of corrosion fatigue in welded joints of test steel are discussed with reference to those of A(587) and A(131) steel. In these experiments, the fatigue damage occurring at all welded joints around the weld interface resulted in the cracks and fractures. The fatigue life of the specimens in seawater with cathodic protection is longer than that in seawater Without protection.

载人潜器串口设备转接工业以太网的实时性建模与分析

根据具体的需求,为载人潜器设计了一种基于工业以太网的内部数据通讯和控制系统,其数据通讯的实时性是衡量控制系统的一个重要指标,因此,为了分析串行数据通信系统的实时性能,据其选用的传感器和网络架构的特点,建立了串口数据包传送时间延迟的数学模型;并在潜器平台上,以实测数据试验误差验证了该模型的准确性和普遍性,从而为开发人员对各种串口设备的参数设置提供理论指导;最后用该模型分析了载人潜器串行数据传送的实时性。

海底金属矿床充水条件及矿坑突水的断层效应研究

The Xinli mine area of Sanshandao mine is adjacent to the Bohai Sea and its main exploitable ore deposit occurs in the undersea rock mass. The mine is the biggest undersea gold mine of China after production. The mine area faces a latent danger of water bursting, even sudden seawater inrush. There is no mature experience in undersea mining in China so far. The vein ore deposit is located in the lower wall of a fault; its possible groundwater sources mainly include bittern, Quaternary pore water and modern seawater. To ensure the safety of undersea mining, to survey the flooding conditions of the ore deposit using proper measures and study the potential seawater inrush pattern are the key technical problems. With the Xinli mine area as a case study, the engineering geological conditions of the Xinli mine area are surveyed in situ, the regional structural pattern and rock mass framework characteristics are found out, the distribution of the structural planes are modeled by a Monte Carlo method and the connectivity coefficients of rock mass structural planes are calculated. The regional hydro-geological conditions are analyzed and the in-situ hydro-geological investigation and sampling are performed in detail, the hydrochemistry and isotopes testing and groundwater dynamic monitoring are conducted, the recharge, runoff, discharge conditions are specified and the sources of flooding are distinguished. Some indices are selected from the testing results to calculate the proportion of each source in some water discharge points and in the whole water discharge of the Xinli mine area. The temporal and spatial variations of each water source of the whole ore deposit flooding are analyzed. According to the special project conditions in the Xinli mine area, the permeability coefficient tensors of the rock mass in Xinli mine area are calculated based on a fracture geometry measurement method, in terms of the connectivity and a few hydraulic testing results, a modified synthetic permeability coefficient are calculated. The hydro-geological conceptual and mathematical model are established，the water yield of mine is predicted using Visual Modflow code. The spreading law of surrounding rock mass deformation and secondary stress are studied by numerical analysis; the intrinsic mechanism of the faults slip caused by the excavation of ore deposit is analyzed. The results show that the development of surrounding rock mass deformation and secondary stress of vein ore deposit in the lower wall of a fault, is different from that in a thick-big ore deposit. The secondary stress caused by the excavation of vein ore deposit in the lower wall of a fault, is mainly distributed in the upper wall of the fault, one surface subsidence center will occur. The influences of fault on the rock mass movement, secondary stress and hydro-geological structures are analyzed; the secondary stress is blocked by the fault and the tensile stress concentration occurs in the rock mass near the fault, the original water blocking structure is destructed and the permeable structure is reconstructed, the primary structural planes begin to expand and newborn fissures occur, so the permeability of the original permeable structure is greatly enhanced, so the water bursting will probably occur. Based on this knowledge, the possible water inrush pattern and position of the Xinli mine area are predicted. Some computer programs are developed using object-oriented design method under the development platform Visual Studio.Net. These programs include a Monte Carlo simulation procedure, a joint diagrammatizing procedure, a structural planes connectivity coefficient calculating procedure, a permeability tensor calculating procedure, a water chemical formula edit and water source fixture conditions calculating procedure. A new computer mapping algorithm of joint iso-density diagram is raised. Based on the powerful spatial data management and icon functions of Geographic Information System, the pit water discharge dynamic monitoring data management information systems are established with ArcView.

基于MRF模型的油气储层属性随机建模方法研究

Stochastic reservoir modeling is a technique used in reservoir describing. Through this technique, multiple data sources with different scales can be integrated into the reservoir model and its uncertainty can be conveyed to researchers and supervisors. Stochastic reservoir modeling, for its digital models, its changeable scales, its honoring known information and data and its conveying uncertainty in models, provides a mathematical framework or platform for researchers to integrate multiple data sources and information with different scales into their prediction models. As a fresher method, stochastic reservoir modeling is on the upswing. Based on related works, this paper, starting with Markov property in reservoir, illustrates how to constitute spatial models for catalogued variables and continuum variables by use of Markov random fields. In order to explore reservoir properties, researchers should study the properties of rocks embedded in reservoirs. Apart from methods used in laboratories, geophysical means and subsequent interpretations may be the main sources for information and data used in petroleum exploration and exploitation. How to build a model for flow simulations based on incomplete information is to predict the spatial distributions of different reservoir variables. Considering data source, digital extent and methods, reservoir modeling can be catalogued into four sorts: reservoir sedimentology based method, reservoir seismic prediction, kriging and stochastic reservoir modeling. The application of Markov chain models in the analogue of sedimentary strata is introduced in the third of the paper. The concept of Markov chain model, N-step transition probability matrix, stationary distribution, the estimation of transition probability matrix, the testing of Markov property, 2 means for organizing sections-method based on equal intervals and based on rock facies, embedded Markov matrix, semi-Markov chain model, hidden Markov chain model, etc, are presented in this part. Based on 1-D Markov chain model, conditional 1-D Markov chain model is discussed in the fourth part. By extending 1-D Markov chain model to 2-D, 3-D situations, conditional 2-D, 3-D Markov chain models are presented. This part also discusses the estimation of vertical transition probability, lateral transition probability and the initialization of the top boundary. Corresponding digital models are used to specify, or testify related discussions. The fifth part, based on the fourth part and the application of MRF in image analysis, discusses MRF based method to simulate the spatial distribution of catalogued reservoir variables. In the part, the probability of a special catalogued variable mass, the definition of energy function for catalogued variable mass as a Markov random field, Strauss model, estimation of components in energy function are presented. Corresponding digital models are used to specify, or testify, related discussions. As for the simulation of the spatial distribution of continuum reservoir variables, the sixth part mainly explores 2 methods. The first is pure GMRF based method. Related contents include GMRF model and its neighborhood, parameters estimation, and MCMC iteration method. A digital example illustrates the corresponding method. The second is two-stage models method. Based on the results of catalogued variables distribution simulation, this method, taking GMRF as the prior distribution for continuum variables, taking the relationship between catalogued variables such as rock facies, continuum variables such as porosity, permeability, fluid saturation, can bring a series of stochastic images for the spatial distribution of continuum variables. Integrating multiple data sources into the reservoir model is one of the merits of stochastic reservoir modeling. After discussing how to model spatial distributions of catalogued reservoir variables, continuum reservoir variables, the paper explores how to combine conceptual depositional models, well logs, cores, seismic attributes production history.