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In this study, graphene oxide (GO) was prepared by the improved Hummers method, and a synergistically stabilized emulsion of GO and emulsifier was formulated. The best emulsion formula obtained by Response Surface Methodology consists of 1.39‰ GO, and 2.92‰ OP-10; the water-oil ratio is 4:6, achieving an emulsion index of 92.83%. The emulsion still maintained good stability under high temperature and high salt conditions, meeting the environmental requirements of medium and low permeability reservoirs. For injected water flooding, emulsion flooding could increase the oil recovery by 15.41%.

Herein, crack-free photonic crystal templates with enhanced color contrast were first demonstrated by the coassembly of polystyrene (PS) microspheres and graphene oxide (GO). Then, photonic crystal hydrogels (PCHs) with quick responses to temperature and alcohol solution concentration changes were fabricated by photopolymerization of monomers in the gaps of the self-assembled colloidal crystal templates. The structural color of the PCHs changed from yellow to blue within 120 s as the temperature rose from 25 to 40 °C, whereas upon a decrease in temperature from 40 to 25 °C, the structural color changed from blue to yellow. The structural color of the PCHs also shows an obvious response with the concentration of alcohol solution ranging from 40 to 100 wt %. The quick responses of the PCHs' structural color to changes in temperature and alcohol solution concentration are attributed to the temperature sensitivity of poly(

Asymmetric supercapacitors (ASCs) based on a battery-type anode and a capacitive-type cathode have been attracting extensive interest because of their high energy density. Herein, NiO nanosheets are hydrothermally deposited onto a V4C3TX substrate, which are then assembled into a 3D porous heterostructure hydrogel through a graphene oxide-assisted self-convergence hydrothermal process at low temperatures. The resultant hierarchical V4C3TX@NiO-reduced graphene oxide (RGO) hydrogel exhibits an ultrahigh specific capacitance up to 1014.5 F g− 1 at 1 A g− 1. Separately, a defective reduced graphene oxide (DRGO) hydrogel is prepared by a cost-effective hydrothermal procedure followed by cobalt-catalyzed gasification, which shows a higher specific capacitance (258 F g− 1 at 1 A g− 1) than untreated RGO hydrogel (176 F g− 1). These two electrodes are then assembled into an ASC, the device features a stable operating voltage of 1.8 V, a maximum energy density of 86.22 Wh kg− 1 at 900 W kg− 1, along with good cycling stability at 96.4% capacitance retention after 10,000 cycles at 10 A g− 1. This work highlights the unique potential of MXenes-based materials for the construction of high-performance ASCs.

Multiple primary cancers (MPC) occurring in the same individual is considered rare but being increasingly recognized owing to the longer cancer survival nowadays. Despite of accumulating experience in diagnosis, effective treatment remains to be problematic in many scenarios. Genetic testing-based targeted therapy could be an invaluable option for both diagnosis and treatment of such patients. Here we present a 74-year-old male with triple primary cancers including kidney, prostate, and lung with metastatic tumor on the costal bones. The patient visited the hospital for persistent cough and hemoptysis, and a diagnosis of squamous cell carcinoma of the left lung was made by bioptic fiberoptic bronchoscopy. A previous history included renal cancer controlled by Sorafenib and prostate cancer controlled by Goserelin. Radiotherapy and platinum-based chemotherapy failed to help the patient and the tumor size increased over a period of 6 months. In order to seek better therapeutical options, we performed targeted sequencing using the cancerous tissues from his lung, kidney, and prostate cancers. Briefly, the results identified VHL, EGFR, PIK3CA, TP53, and AKT1 mutations in lung cancer, AKT1, FGFR2, and TP53 mutations in renal cancer, and FGFR2 mutations in prostate cancer. A combined medication targeting PIK3CA and AKT1 signaling was recommended and the patient was given BKM120 (PIK3CA, Phase III clinical trial) and MK2206 (AKT, phase III clinical trial). Revisit chest CTs after 4 months and 9 months showed a significant shrinkage of tumor size by 40% and 80%, respectively. Our experience demonstrated a good example that genetic analysis could be valuable to diagnose and precisely treat multiple primary cancers.

Background The architectural transcriptional regulator high-mobility group AT-hook 2 (HMGA2) is an oncofetal protein which has been reported to be ectopically expressed in a variety of cancers. A high expression of HMGA2 in human renal cell carcinoma (RCC) is related with tumor invasiveness and poor prognosis. Recent in vitro studies have shown that HMGA2 knockdown was able to decrease cell proliferation and migration, and regulate the gene expression related to epithelial-mesenchymal transition (EMT). Methods To understand the HMGA2’s effect in vivo, HMGA2 expression was knocked down in ACHN cells using small hairpin RNA (shRNA), then the HMGA2-deficient ACHN cells were xenografted into the BALB/c nude mice. Tumor growth was monitored and the expression of EMT-related genes was analyzed. Results HMGA2 expression was confirmed to be knocked down in the cultured and xenografted ACHN cells. The xenograft tumor of HMGA2-deficient cells demonstrated a retarded growth pattern compared with the control. The expression of E-cadherin was increased, whereas N-cadherin and Snail were decreased in the HMGA2-deficient xenograft tumors. Conclusions In conclusion, to the best of our knowledge, for the first time, we have successfully developed an in vivo experiment using HMGA2-silencing ACHN cells to be grown as xenografts in nude mice. Our findings show that HMGA2 deficiency was sufficient to suppress the xenograft tumor growth in vivo, which support our hypothesis that HMGA2-induced renal carcinogenesis occurs at least in part through the regulation of tumor associated EMT genes.

Demulsifiers are considered the key materials for oil/water separation. Various works in recent years have shown that demulsifiers with polyoxypropylen epolyoxyethylene branched structures possess better demulsification effects. In this work, inspired by the chemical structure of demulsifiers, a novel superhydrophilic/underwater superoleophobic membrane modified with a polyoxypropylene polyoxyethylene block polymer was fabricated for enhanced separation of O/W emulsion. First, a typical polyoxypropylene polyoxyethylene triblock polymer (Pluronic F127) was grafted onto the poly styrene-maleic anhydride (SMA). Then, the Pluronic F127-grafted SMA (abbreviated as F127@SMA) was blended with polyvinylidene fluoride (PVDF) for the preparation of the F127@SMA/PVDF ultrafiltration membrane. The obtained F127@SMA/PVDF ultrafiltration membrane displayed superhydrophilic/underwater superoleophobic properties, with a water contact angle of 0° and an underwater oil contact angle (UOCA) higher than 150° for various oils. Moreover, it had excellent separation efficiency for SDS-stabilized emulsions, even when the oil being emulsified was crude oil. The oil removal efficiency was greater than 99.1%, and the flux was up to 272.4 L·m−2·h−1. Most importantly, the proposed F127@SMA/PVDF membrane also exhibited outstanding reusability and long-term stability. Its UOCA remained higher than 150° in harsh acidic, alkaline, and high-salt circumstances. Overall, the present work proposed an environmentally friendly and convenient approach for the development of practical oil/water separation membranes.

Based on 2018 China's Human Resource Employees Survey Data, this study uses the probit model to examine the impact of entrepreneurial ability and career development on HR's entrepreneurial intention. In terms of entrepreneurial ability, the results show that the educational background of Human Resource Management, cross-disciplinary knowledge, job-hopping experience, and the number of subordinates have significant positive impacts on HR's entrepreneurial intention. In terms of career development, lack of promotion space, skill upgrading opportunities, and lower than expected income have significant positive impacts on HR's entrepreneurial intention, and these impacts are heterogeneous among different enterprises. This study suggests that potential entrepreneurs can be identified from the explicit characteristics, which reflect HR's entrepreneurial abilities, and it is necessary to face up to the influence of career development on HR's entrepreneurial intention and encourage them to participate in on-the-job entrepreneurship. This study suggests that HR's entrepreneurial ability should be regarded as an important starting point for entrepreneurial success, and it is necessary to improve HR's career development system to create more opportunities for on-the-job entrepreneurship, and government should implement differentiated and precise entrepreneurial support policies to encourage HR's entrepreneurship.

To solve the coating’s defects and achieve the goal of lightweight heavy-duty anticorrosive coatings, various two-dimensional (2D) nanomaterials are introduced to polymeric coatings to prepare long...

Inspired by mussels’ universal adhesive ability to various substrates, polydopamine (PDA) was used to bind graphene oxide (GO) and hexagonal boron nitride (h-BN) together to fabricate h-BN-rGO@PDA nanohybrids. The as-prepared h-BN-rGO@PDA nanohybrids were served as anticorrosive nanofillers for polyvinylbutyral (PVB) coatings on mild steel. The structure of h-BN-rGO@PDA nanohybrids were characterized by SEM, XRD, FT-IR, UV–vis and Raman spectroscopies. Electrochemical corrosion tests were conducted to examine the anticorrosion properties of h-BN-rGO@PDA/PVB composite coatings. The results show that the stacked h-BN nanosheets are exfoliated by GO. And PDA is successfully grafted onto the surface of h-BN-rGO@PDA and simultaneously reduced GO into rGO. The h-BN-rGO@PDA nanohybrids are homogeneously distributed in the PVB matrix. When the mass ratio of GO to h-BN in h-BN-rGO@PDA is 1:1, the as-prepared h-BN-rGO@PDA possesses effective aspect ratio and thus its PVB composite coating obtains the optimal anticorrosion performance with 2 orders of magnitude higher than pure PVB.

The angle dependence, easy cracking and weak mechanical properties of structural color coatings from colloidal crystals bring great challenges to their practical application. In this work, crack-free structural color coatings with non-iridescence were prepared on the surface of calcium silicate board (CSB) for the first time by co-assembling polydopamine-wrapped polystyrene nanoparticles (PS@PDA NPs) and polyacrylate (PA). The effect of dopamine hydrochloride amount on the saturation of the structural color of PS@PDA was discussed, and there were cracks in the surface of the coatings. The addition of PA greatly inhibited the formation of cracks during PS@PDA assembly and had almost no effect on the saturation of the structural colors. In addition, after the surface had been brushed with waterborne wood paint, the coatings had good chemical and mechanical stability, and the non-iridescence of the structural color coatings was not affected. This research would provide a new reference to fabricate bright non-iridescent structural color coatings with good mechanical features on man-made boards, which could promote the potential applications of structural colors in decorative field and other fields.

Purpose: To determine the rate and extent of the maternal–fetal transplacental passage of bromocriptine (BCT) in the dually perfused human placental model.Methods: Twenty term placentas were includ...

While tick-borne zoonoses, such as Lyme disease and tick-borne encephalitis, present an increasing global concern, knowledge of their vectors’ distribution remains limited, especially for China. In this paper, we present the first comprehensive dataset of known tick species and their distributions in China, derived from peer-reviewed literature published between 1960 and 2017. We searched for journal articles, conference papers and degree thesis published in both English and Chinese, extracted geographic information associated with tick occurrence, and applied quality-control procedures to remove duplicates and ensure accuracy. The dataset contains 5731 records of geo-referenced occurrences for 123 tick species distributed over 1141 locations distinguished at four levels of scale i.e., provincial, prefectural, county, and township and finer. The most frequently reported tick species include Haemaphysalis longicornis, Dermacentor silvarum, Ixodes persulcatus, Haemaphysalis conicinna, Rhipicephalus microplus, and Rhipicephalus sanguineus sensu lato. The geographical dataset provides an improved map of where ticks inhabit China and can be used for a variety of spatial analyses of ticks and the risk of zoonoses they transmit., Design Type(s)disease state design • data integration objective • pathogenicity designMeasurement Type(s)Scientific PublicationTechnology Type(s)digital curationFactor Type(s)geographic location • temporal_interval • SpeciesSample Characteristic(s)Ixodida • China Machine-accessible metadata file describing the reported data (ISA-Tab format)

The lithium transition-metal phosphate LiFe0.6Mn0.4PO4 has two operating potentials, 3.5 V and 4.1 V, which is favorable for increasing the energy and power densities of lithium-ion batteries (LIBs). To study the compatibility between LiFe0.6Mn0.4PO4 and electrolytes, lithium bis(oxalate)borate (LiBOB) is chosen as the lithium salt, based upon ethylene carbonate (EC), dimethyl carbonate (DMC), and dimethyl sulfite (DMS) as the supporting electrolyte solvents. The electrochemical performances of lithium hexafluorophosphate (LiPF6)-based and LiBOB-based electrolytes are compared. The combination of LiBOB and DMS can facilitate the formation of an effective passivation film. In addition, LiBOB-EC/DMS electrolyte exhibits better cycle and rate performance. The results suggest that LiBOB-EC/DMS electrolyte has good compatibility with LiFe0.6Mn0.4PO4, which makes it an attractive electrolyte for rechargeable LIBs based upon LiFe0.6Mn0.4PO4 cathodes.

To develop a convenient way to functionalize graphene oxide (GO) for corrosion protective coatings, a commercial acrylate phosphorus functional monomer (SIPOMER PAM100) was used to modify thiol-terminated GO via thiol-Michael addition click reaction. Subsequently, PAM100 modified GO (PGO) was introduced to waterborne epoxy coating as a nanofiller for anticorrosion reinforcement. The anticorrosive performance of PGO/WEP nanocomposite coatings was evaluated by electrochemical impedance spectroscopy (EIS). Results obtained from FT-IR, XRD, Raman, SEM and SEM-EDS show that PAM100 is successfully grafted to the surface of GO using γ-Mercaptopropyl triethoxysilane (KH-580) as a bridge molecule. It is clear that PGO distributes homogenously within WEP matrix from SEM images. After 40-day exposure to 3.5 wt.% NaCl solution, the |Z|0.01Hz of blank WEP suffers a serious decrease (from 9.83 × 107 Ω·cm2 to 4.93 × 106 Ω·cm2) while PGO/WEP has a relatively smaller change in |Z|0.01Hz (from 1.35 × 108 Ω·cm2 to 2.91 × 107 Ω·cm2). It demonstrated that PGO/WEP coating presents a superior corrosion resistance performance.

In this study, α-zirconium phosphate (α-ZrP) is used as an accelerator for phosphate coatings on carbon steel. A more compact phosphate coating with enhanced corrosion resistance is obtained with the incorporation of α-ZrP. Scanning electron microscopy (SEM) was used to observe the growth of phosphate crystals and the surface morphology of phosphate coatings during the phosphating process. The phosphate crystals composition was analyzed by X-ray diffraction (XRD) spectra. Coating weight and surface roughness tests were also performed. Results of all these characterizations reveal that the incorporation of α-ZrP reduces the phosphate crystals size, coating weight and decreases coating roughness. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests demonstrate that the incorporation of α-ZrP effectively improves corrosion resistance of phosphate coatings (i.e. the corrosion rate is decreased by one order of magnitude). Optimally when the concentration of α-ZrP in the phosphating solution is 0.8 g/L, the minimum corrosion rate (0.17 mpy) is obtained.

This study reports an eco-friendly waterborne epoxy (WBE) coating with excellent corrosion resistance by adding ammonium grafted graphene oxide (AGO) as co-dispersant. AGO, as a co-dispersant, addresses the problem of a lot of micro-defects caused by the intrinsic mismatch between epoxy resin and amine curing agents during the formation of aqueous epoxy resin. Also, the compatibility of GO in the epoxy resin matrix is also improved by the ammonium modification. The ammonium modification process was systematically studied using Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD) spectra, UV–vis spectra, Raman spectra and X-ray photoelectron spectra (XPS). Scanning electron microscope (SEM) images show that AGO sheets has successfully inhibited the formation of micro-pores and micro-defects, forming a more compact WBE/AGO composite coating. As a result, the corrosion resistance of the coating has been greatly improved as investigated by the potentiodynamic polarization test. The corrosion rate of WBE/AGO is decreased by three orders of magnitude compared to pure WBE coating. The corrosion protection mechanism of the WBE/AGO coating is studied via Electrochemical impedance spectroscopy (EIS) test, and equivalent electrical circuits are applied to fitting the EIS results and reveal the effect of AGO in the composite coating.

Having high aspect ratio and excellent gas barrier property, two dimensional α-zirconium phosphate nanosheets (α-ZrP) are one of the promising anticorrosive nanofillers. In this work, under mild conditions, layered α-ZrP were effectively exfoliated by Tris buffer solution and functionalized by situ polymerization of polydopamine (PDA) in one pot. And then the functionalized α-ZrP (f-ZrP) were introduced into waterborne epoxy (WEP) coatings that were applied on the mild steel for electrochemical corrosion tests. Results of TEM, XRD and AFM reveal that α-ZrP are successfully exfoliated with an interlayer space of 1.72 nm and a thickness of 0.78 nm. Characterizations of FTIR spectra, TEM image and EDS mapping confirm that α-ZrP are decorated by PDA. With PDA decoration, f-ZrP gain a better compatibility with WEP than pristine α-ZrP do, leading to a homogeneous distribution in the polymer matrix. And the exfoliation by Tris buffer provides f-ZrP with high aspect ratio, which is beneficial for f-ZrP/WEP to fight against the permeation of corrosive mediums. Therefore, after 15-day immersion in 3.5 wt% NaCl solution, the f-ZrP/WEP composite coatings show high value of |Z0.01Hz| (1.90 × 107 Ω·cm2), which is about one order of magnitude over that of blank WEP coatings (2.33 × 106 Ω·cm2).

Developing drilling fluids with good bentonite suspension stabilities in saline water-based muds are preferred for sufficient cutting carrying capacities, lower filtration loss, and better shear-thinning behavior. In this work, the salt-tolerant bentonite (STB) was prepared by bentonite, composite fiber materials, and other additives. The results indicated that the drilling fluids of STB had excellent rheological and filtration properties in brine compared with drilling fluids of attapulgite. The ratio of yield point to plastic viscosity (RYP) of 6.4%STB in brine was suitable for drilling operation, while the RYP of 6.4%bentonite was almost 0 Pa/(mPa·s). The salt-tolerant properties of different materials including fiber materials, polyanionic cellulose, and so on were investigated. The fiber materials played an essential role in improving the stability of bentonite particles. Aiming to improve cost-efficiency, the cotton fibers were investigated to replace a certain dosage of asbestos fibers. The cotton was modified by 10wt% NaOH solution to resolve the compatibility problem with asbestos. The rheological modifier prepared from composite fibers has been successfully used in Dagang Oilfield, China. The rheological modifier increased the viscometer dial reading of θ6 and θ3 of drilling mud from 5 dia and 4 dia to 8 dia and 6 dia, which could significantly improve the suspension capacities of the mud.

The objective of the study was to determine transplacental of oseltamivir phosphate (OP) and its active metabolite oseltamivir carboxylate (OC) using the ex vivo human placental perfusion model in Chinese Hans population.Perfusion studies were performed on 20 placentas from healthy term pregnancies. Concentrations typical for 75 mg, twice-daily oral dose were tested (OP 65.2 ng/ml and OC 348 ng/ml), along with the positive control antipyrine 0.1 mg/ml. Each perfusion experiment was conducted for 180 min while samples were taken from both maternal and fetal compartments. Concentrations of OP and its metabolite OC were determined by ultrafast-performance liquid chromatography/tandem mass spectrometry. Integrity and viability of the placenta were determined by measuring fetal volume loss, pH, pOFollowing 3 h of perfusion, the fetal transfer rates of OP and its metabolite OC were 12.39%±3.26%, 10.17%±2.03%, respectively. The clearance indexes of OP and OC were 0.36 ± 0.11 and 0.29 ± 0.06, respectively.These data suggest that OP and its metabolite OC pass through the healthy term placenta at a small amount according to the ex vivo human placental perfusion model, fetal exposure must be considered when treating pregnant women with OP.

Olivine LiMn0.4Fe0.6PO4 (LMFP) materials were synthesized by the modified sol–gel method with the addition of sucrose as an additional carbon source. Electrochemical properties of LMFP were advanced. The materials doped possess high reversible capacity of 107.4 mAh·g at 0.2 C-rate and excellent cycling stability (the capacity retention of 85.8% via 50 cycles), exhibiting the improved electrochemical properties. Introduction Currently, energy and environment are the most important topics. One of the greatest challenges is how to make use of Green Energy according to the strategy of sustainable development and the replacement of fossil fuels [1]. During the past decades, lithium ion batteries (LIBs) have dominated the portable electronic market and been applied to electric vehicles (EVs), hybrid EVs (HEVs) and smart grids, due to their high energy density and safety [2, 3]. All the time, lithium transition metal oxides are used as the main cathode active materials. However, these materials have some limitations for the intrinsic drawbacks, such as a poor thermal stability [4]. For this reason, the olivine-LiMPO4 (M =Mn, Fe, Co, Ni) compounds are drawing more and more interests owing to their low cost, environmentally benign nature, high capacity and thermal stability. As a promising candidate, lithium manganese phosphate LiMnPO4 is expected for its high energy density (700 Wh/kg) and aboundant resource [5]. Unfortunately, LiMnPO4 is being affected by the actual defect, such as slow lithium diffusion kinetics, low electronic and polaronic conductivity. In addition, the high structural strain at the phase boundary between charged and discharged phase and the instable structure due to Jahn-Teller distortion of Mn ion limit its application [6, 7, 8]. Hence, many efforts have been conducted to improve its properties. Recently, partial substitution by transition metal in LiMnPO4 is employed to achieve high energy density and stability. Indeed, some researches demonstrate an increase in kinetics when some of the Mn ions are replaced with Fe to form the solid solution LiMnxFe1-xPO4 [9]. Therefore, the solid solutions with an olivine structure is regarded as a promising material. What is more, the partial substitution of Mn ions by Fe ions can effectively improve the specific and rate capabilities, which may be attributed to the excellent contact area between active materials and electrolyte [10, 11]. In this work, we synthesize the LMFP utilizing Fe substitution by sol-gel method and investigate improved performance of LMFP, principally. LiMnPO4 sample is prepared as a comparison, as well. The results indicate that iron substituted lithium manganese phosphate exhibits distinctly improved electrochemical properties, compared to the simple lithium manganese phosphate. Experimental LiMn0.4Fe0.6PO4 was prepared by the modified sol-gel method, reported in a previous study [12]. All reagents were analytical grade. LiH2PO4, FeC2O4·2H2O, Mn(COOCH3)2·4H2O were dissolved in deionized water in the correct stoichiometric ratios to get a mixed solution, and a critic 5th International Conference on Environment, Materials, Chemistry and Power Electronics (EMCPE 2016) © 2016. The authors Published by Atlantis Press 342 acid solution was added to the preceding solution. Sucrose was added as an additional carbon source. After placed in oil bath at 80 °C for 10 h, the mixture was dried at 100 °C for 12 h in a vacuum oven. Finally, the gel was calcined at 700 °C for 10 h to obtain the composite. The structure was characterized by powder X-ray diffraction (XRD, Rint-2000, Rigaku, Japan) using Cu-Kα radiation over the 2θ range of 10°-80°. Electrochemical tests were performed by the coin cells (2032 type) that were assembled in an argon glove box. The cathode materials were formed from the active materials, a poly (tetrafluoroethylene) binder and acetylene black in 80:10:10 weight ratio. 1 M LiPF6 dissolved in a mixture of ethylene carbonate and dimethyl carbonate (1:1 vol. %) was used as the electrolyte between the lithium metal anode and the cathode. The capacities and cycle performances of the cells were carried out on a LAND CT2001A tester (Wuhan, China) in the voltage range of 2.5-4.5 V. Electrochemical impedance spectroscopy (EIS) was conducted over a frequency range of 10 kHz to 10 mHz, with a 5 mV a.c. input signal by CHI660C (Shanghai, China). Results and discussion 10 20 30 40 50 60 70 80 2 theta (degree) PDF#77-0178 In te ns ity (a .u .) x=1 x=0.4 LiMnxFe1-xPO4 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 2.0 2.5 3.0 3.5 4.0 4.5 5.0

In order to utilize the produced liquid of hydrolyzed polyacrylamide (HPAM) flooding to enhance oil recovery, the interaction between hydrophobically modified polyacrylamide (HMPAM) and the produced liquid of HPAM flooding was investigated. The viscous characteristic of HMPAM in aqueous solution was investigated by Ubbelohde viscometer. The results show the intrinsic viscosity of HMPAM in aqueous solution is higher than that of HPAM, indicating that HMPAM has better effect on increasing the viscosity of aqueous solution. The viscosity of the complex system consisted of HMPAM and the produced liquid from HPAM flooding is lower than that of the HMPAM system, but higher than that of the HMPAM/HPAM complex system in mineralized water. In order to investigate the major factor of the influence on the viscosity of the HMPAM/produced liquid complex system, the viscosities of HMPAM/HPAM (and hydrolyzed HPAM with different hydrolysis degree) in distilled water and in mineralized water were studied. The fluorescence...

A new AC-DC-AC matrix converter topology based on Cuk is proposed. The basic configuration of the new topology and its fundamental principle are firstly introduced, the analytic expression on the function of voltage transfer ratio and duty cycle is analyzed, and the rationale of double-loop control strategy is clarified. Finally the validity and feasibility of the new topology are tested by means of computer simulation and prototype experiment. The results indicate that the regulation of the voltage transfer ratio and of the output frequency can be adequately implemented by these new converters with low harmonic distortions of waveform. This study suggests that the problem of low voltage transfer ratio, which has been an inherent drawback of the traditional MCs, can be effectively overcome, and the approach may provide inspiration for further engineering application.

The laboratory performance properties of the colloidal dispersion system are described in the proposed paper. This paper deals with the improvement and application of a new technology to EOR. This technology is applicable to high salinity, high temperature and severe heterogeneity reservoir. The essence of this technology is to decrease the water cut of production wells and attain the result of oil production and recovery enhancement by injecting an improved micelle dispersions system. According to lab test, this colloidal dispersion system is a pseudoplastic fluid with temperature tolerance, salinity tolerance, shearing resistance, stability and low cost. The lab experiment result shows oil recovery is improved by 8—10%. The information of lab study and field application relative to this technology has been presented at the 2000 International Symposium on Petroleum Engineering. The previous technology has a defect of crosslinking to polymer's wide applicability, now this system has been improved in its properties. The new micelle dispersions system can satisfy all polymer in use and form stable weak gel system. It can keep stable when reservoir temperature is 90°C, water salinity is 80000mg/L (Ca2++Mg2+≤ 2000mg/L). A pilot was conducted in fault—block Xin 50 of Dongxin oil field. There are 4 injection wells and 7 corresponding production wells.in the area The viscosity of aimed formation oil is 80mPa.s, the temperature is 90 °C, the salinity of reservoir is 44100mg/L, well spacing is 300m. Some production wells were effective after 2 months injection during the successive injection of this improved micelle dispersions system. Water cut of typical effective well was decreased by 34.1%. Oil production per day increased 30 ton. Pilot test shows that this technology has better enlarge commercial application potentiality and economic value. It will be applied in others similar blocks on great scale in the future.

A new EOR method of Crosslinked polymer displacement technology is introduced in this paper. The crosslinked system is based on the reaction of Cr(III) in crosslinker with hydrolysed polyacrylamide(HPAM). After gelation, the system has some character such as good viscoelasticity, good thermal stability, and high salinity resistance. The viscoelasticity of crosslinked system can reach 2–3 times simple polymer solution. As a new system combining profile modification and flooding, it can be applied in high water-cut and severe heterogeneous reservoirs. Because of delayed crosslinking property, it can not only improve profile during injection, but also flow increase volumetric sweep efficiency. Having been injected into reservoir, crosslinking polymer can block and adjust high permeability zones in deep section, and improve sweep volume, and decrease water to oil mobility ration, thereby enhance recovery efficiency. The pilot is is in BO-19 block in GUDAO oilfield, which is characteristic of positive rhythm deposit, loosed sand cement, high density and high viscosity etc. The reservoir temperature is 73°C, the viscosity of crude oil is 80mPa.s, density is 0.9030g/cm3 at reservoir conditions, permeability is 1000–2000×10−3μm2 and the formation water salinity is 6453mg/L. It has 21 injection wells and 40 production wells, the oil-bearing area is about 2.4km2 and reserve in place is about 737.3×104 tons. From 1999 to 2001, 0.15PV (pore volumes) of crosslinked polymer solution has been injected, and a good effect of increasing oil and decreasing water appears, oil production increases from 201 to 350 tons per day, composite water cut decreases from 91.3% to 84.6%, cumulative incremental oil reached 5.0×104tons.