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During the pore-forming stage of floor heave treatment, the phenomenon of gravel sediment accumulation in the bottom hole often occurs, which causes great difficulties in the normal installation of the anchor cable. Based on this observation, a new anchor cable installation method was proposed, which involves installing a drill bit at the front end of the anchor cable to assist its drilling. With the help of an anchor cable drilling test bench, the influence of the bit, motion parameters, and hole environment on the performance of anchor cable drilling was studied. Through the co-simulation of the discrete element method (i.e., multibody dynamics (DEM-MBD)), the drilling process of the bit anchor cable was simulated, and the dynamic characteristics of the bit anchor cable drilling in the bottom hole gravel sediment were analysed. The results show that installing a drill bit in front of the anchor cable can greatly reduce the drilling resistance and hamper torque during anchor cable drilling. When the rotational direction of the bit anchor cable is consistent with the spiral direction of the anchor cable, the bit anchor cable can exhibit better drilling performance. The drilling resistance and hindering torque of the bit anchor cable are the largest when drilling in soaked particles, followed by drilling in dry particles, and the smallest occurs when drilling in moist particles. The research results can provide reference for the parameter setting of anchor cable auxiliary installation equipment.

Some inpatients with HIV-RNA ≥500,000 copies/mL in China need to use 2-drug regimen for some reasons, although limited data are available for dolutegravir plus lamivudine (3TC) in those patients with ultra-high viral loads.We conducted a single-center retrospective-prospective study in China and enrolled 42 ART-naive HIV-infected inpatients who use a once-daily 2-drug regimen because of various reasons (drug interaction, renal impairment, age, and other related comorbidities).They were divided into 2 groups, low viral load group (baseline viral load500,000 copies/mL, n = 20) and high viral load group (baseline viral load ≥500,000 copies/mL, n = 22). All patients were followed up for 48 weeks.The median of baseline viral load was 5.74 log10 copies/mL and CD4+ T-cell count was 59 cells/μL. At week 48, there was no significant difference (P = 0.598) in proportions of participants with HIV-1 RNA50 copies/mL [90%, 95% confidence interval (CI) (75.6% to 104.4%) in low viral load groups vs 95.5%, 95% CI (86.0% to 104.9%) in high viral load groups]. No differences were found in mean increase of CD4+ T-cell count from baseline between 2 groups (218 ± 122 vs 265 ± 127 cells/μL, P = 0.245). There is no grade 3 or higher treatment-related adverse events and none discontinued treatment because of adverse events.The results of our study in real world support dolutegravir + 3TC dual regimen as a promising therapy option for treatment-naive HIV-infected patient with baseline viral load ≥500,000 copies/mL.

Ultrasonic flotation is useful for fine low-rank coal purification; however, the efficiency of ultrasonic flotation still needs to be improved. Because the dynamic behavior of flotation bubbles has significant effects on their flotation efficiency, it was investigated under different gas input conditions with and without ultrasound using the volume of fluid method and h-speed imaging. The results indicated that the gas input method can influence the final kinetic behavior of the flotation bubbles by changing the morphology of the initial bubble. With an increase in the size and aspect ratio of the bubble, the bubble deformation and velocity increased, and the range of motion of the bubble increased and then decreased. Meanwhile, the size of the bubble increased with an increase in the thickness of the vibrating plate of the ultrasonic transducer owing to the aggregation of the bubbles under the influence of ultrasound.

In this work, vanadium particles (VP) were utilized as a novel reinforcement of AZ31 magnesium (Mg) alloy. The nanocrystalline (NC) AZ31–VP composites were prepared via mechanical milling (MM) and vacuum hot-press sintering. During the milling process, the presence of VP contributed to the cold welding and fracture mechanism, resulting in the acceleration of the milling process. Additionally, increasing the VP content accelerated the grain refinement of the matrix during the milling process. After milling for 90 h, the average grain size of AZ31-X wt % Vp (X = 5, 7.5, 10) was refined to only about 23 nm, 19 nm and 16 nm, respectively. In the meantime, VP was refined to sub-micron scale and distributed uniformly in the matrix, exhibiting excellent interfacial bonding with the matrix. After the sintering process, the average grain size of AZ31-X wt % VP (X = 5, 7.5, 10) composites still remained at the NC scale, which was mainly caused by the pinning effect of VP. Besides that, the porosity of the sintered composites was no more than 7.8%, indicating a good densification effect. As a result, there was little difference between the theoretical and real density. Compared to as-cast AZ31 Mg alloy, the microhardness of sintered AZ31-X wt % VP (X = 5, 7.5, 10) composites increased by 65%, 87% and 96%, respectively, owing to the strengthening mechanisms of grain refinement strengthening, Orowan strengthening and load-bearing effects.

The effect of calcium ions on the separation of scheelite from fluorite was studied using atomic force microscopy (AFM) measurement, X-ray photoelectron spectroscopy (XPS) analysis and micro-flotation experiment. The XPS results confirmed the adsorption of calcium on scheelite and fluorite surface, and adsorption difference existed between calcium solution and gypsum solution. According to the AFM results, the adhesion forces between scheelite and fluorite would increase in the presence of calcium, so did the corresponding jump-in distance and separation distance. Besides, jump-in distance and separation distance in calcium solution were larger than those in gypsum solution. When using sodium silicate as depressant, the adhesion forces between scheelite and fluorite decreased observably, while regained in the presence of calcium ions. Micro-flotation results confirmed the depression of calcium on scheelite and fluorite. Besides, both scheelite and fluorite were depressed strongly by sodium silicate in the presence of calcium. These indicated that the adsorption of CaOH+ would increase their hydrophilicity and enhance the interaction forces. Meanwhile, the selectivity of sodium silicate was depressed in the presence of calcium ions. The combined results could help to understand how calcium-mineral surface properties would cause the difficult separation.

Based on 2D fractal dimension, the effect of aluminum ion (Al3+) on kaolinite flocculation using anionic polyacrylamides (APAMs) as flocculant has been investigated at pH 4. The settling performance was tested, and fractal dimensions of flocs were analyzed. The results show that the clearer the supernatant, the bigger fractal dimension was obtained using APAM in distilled water. With the addition of Al3+, the supernatant turbidity increases first and then decreases, while the trend of fractal dimension with Al3+ concentration is opposite. Zeta potential results indicate that different sedimentation performance and floc fractal dimension of kaolinite are caused by the different APAM flocculation mechanism.

Calcium ions are common in flotation process water, and have a significant effect on the molybdenite floatability, making separation of molybdenite from other minerals more difficult. Therefore, to improve the separation selectivity, the research of how calcium ions affect the molybdenite surface properties is of great significance. In this study, various methods including flotation tests, contact angle measurements, batch adsorption tests and Density Functional Theory (DFT) simulations were carried out to understand the adsorption characteristics and mechanism. Results of the contact angle measurements showed that the inhibition effects of calcium ions on molybdenite flotation kinetics were mostly attributed to the decrease of the edge surface hydrophobicity, as the contact angle of the edge surface decreased more than the face surface after treatment with calcium ions. While fitting the results of batch adsorption tests with adsorption kinetics and isotherm models, it was found that the Lagergen pseudo-first-order equation and the Freundlich isotherm model nicely follow the experimental trend. Moreover, DFT calculation results indicated that both Ca2+ and CaOH+ preferentially adsorb on the molybdenite (100) surface, particularly the edge surface, which was consistent with the contact angle results. Ca2+ adsorbed on the Mo-top site on the S-(100) surface by forming Ca-S bonds, transferring electrons from Ca 3d orbitals to S 3p orbitals. CaOH+ adsorbed on the S-top site of Mo-(100) surface by forming a strong covalent Mo-O bond and S-Ca bond. The results provide a basis for understanding and improving the separation effect of molybdenite from other minerals in the presence of calcium ions.

Nasopharyngeal carcinoma is one of the most common malignant neoplasms in head and neck. In this work, surface-enhanced Raman spectroscopy technique was used to study the molecular differences betw...

Physicochemical Problems of Mineral Processing; ISSN 2084-4735

Gold (Au) nanoparticles were introduced into thin films of layered cobaltites to decrease the sheet resistance and improve the transparent conducting performance of the films. c-axis-oriented Bi2Sr2Co2O8 thin films dispersed with Au particles with diameters of about 5–10 nm were obtained by pulsed laser ablation of a Bi2Sr2Co2O8 ceramic target on which a piece of fan-shaped Au foil was attached. The resulting Bi2Sr2Co2O8/Au composite thin films, with the Au concentration of about 1.6 at.%, showed a very low resistivity of about 3.0 mΩ cm at room temperature and a reasonable optical transmittance of about 48 % in the visible range, resulting in a high figure of merit of about 2270 MΩ−1. This value is comparable to those reported for the state-of-the-art p-type transparent conducting oxides and is about 1.7-fold higher than that of the pure Bi2Sr2Co2O8 thin films.

High wavenumber (HW) Raman spectroscopy has weaker fluorescence background compared with fingerprint (FP) region. This study aims to evaluate the discrimination feasibility of nasopharyngeal non-cancerous and nasopharyngeal cancer (NPC) tissue with both FP and HW Raman spectroscopy. HW Raman spectra of nasopharyngeal tissue were obtained for the first time. Raman spectra were collected to differentiate nasopharyngeal non-cancerous (n = 37) from NPC (n = 41) tissues in FP (800–1800cm−1), HW (2700–3100cm−1), and integrated FP/HW region. First, to assess the utility of this method, the averaged Raman spectral intensities and intensity ratios of corresponding Raman bands were analyzed in HW and FP regions, respectively. The results show that intensities as well as the ratios of specific Raman peaks might be helpful in distinguishing nasopharyngeal non-cancerous from NPC tissue with the HW Raman spectroscopy, as with FP Raman reported before. The multivariate statistical method based on the combination of principal component analysis–liner discriminant analysis (PCA-LDA), together with leave-one-patient-out, cross-validation diagnostic algorithm, was used for discriminating nasopharyngeal non-cancerous from NPC tissue, generating sensitivities of 87.8%, 85.4%, and 95.1% and specificities of 86.5%, 91.9%, and 89.2%, respectively, with Raman spectroscopy in the FP, HW, and integrated FP/HW regions. The posterior probability of classification results and receiver operating characteristic curves were utilized to evaluate the discrimination of PCA-LDA algorithm, verifying that HW Raman spectroscopy has a positive effect on the differentiation for the diagnosis of NPC tissue by integrated FP/HW Raman spectroscopy. What's more, the potential of Raman spectroscopy used for differentiating different pathology NPC tissues was also discussed. The results demonstrate that both FP and HW Raman spectroscopy have the potential for diagnosis and detection in early nasopharyngeal carcinoma, and HW Raman spectroscopy may improve the discrimination of NPC tissue compared with FP region alone, providing a promising diagnostic tool for the diagnosis of NPC tissue. Copyright © 2015 John Wiley & Sons, Ltd.

Termites are responsible for an estimated US$1 billion annually in property damage, repairs, pest control, and prevention. There is an urgent need of finding a better alternative way to control and prevent termites. Port-Orford-Cedar (POC) has been known to have significant levels of natural durability and termiticidal activities due to its extractive contents. In this study, 25 endophytes including 22 fungal and 3 bacterial strains were isolated from the POC. Four strains, namely, HDZK-BYF21, HDZK-BYF1, HDZK-BYF2, and HDZK-BYB11, were chosen to test their termiticidal activities. The fermentation broth of strain HDZK-BYF21 displayed the potent antimicrobial and termiticidal activities. Morphological examination and 18 S rDNA sequence analysis demonstrated that strain HDZK-BYF21 belonged to the genus Aspergillus. This finding indicates the existence of an interesting chemical symbiosis between an endophytic fungus and its host. This is also the first report on endophytes isolated from the POC that may have potential termiticidal activities. Endophytes with termiticidal activities can be grown in bioreactor to provide an inexhaustible supply of bioactive compounds and thus can be exploited commercially.

Light-induced transverse thermoelectric effect is investigated in incline-oriented Bi2Sr2Co2Oy thin films covered with a graphite light absorption layer. Upon the illumination of a 980 nm cw laser, an enhanced voltage signal is detected and the improvement degree is found to be dependent on the thickness of the graphite layer. A two-dimensional (2D) heat transport model using the finite-difference method provides a reasonable explanation to the experimental data. Present results give some valuable instructions for the design of light absorption layers in this type of detector.

p-type transparent conductive Ca3Co4O9 thin films were grown on LaAlO3 substrates using a pulsed laser deposition technique. The films showed perfect c-axis orientation with a resistivity of about 7.3 mΩ cm at room temperature and optical transmittance of about 50% in the visible range. A high figure of merit of about 988 MΩ−1 was achieved in these c-axis oriented Ca3Co4O9 films, which is comparable to those reported for the state-of-the-art p-type transparent conducting oxides. This work demonstrated the potential applications of c-axis oriented Ca3Co4O9 films in optoelectronic devices as a new class of transparent conducting oxide coatings.

This article briefly reviews the applications of Raman spectroscopy technology for nasopharyngeal cancer tissue detection, especially presenting the corresponding work of our group in Fujian normal university, and discussing the perspective of this field.

c-Axis oriented Bi2Sr2Co2Oy thin films imbedded with Au nanoparticles were prepared by pulsed laser ablation a ceramic Bi2Sr2Co2Oy target with a small piece of Au foil overlapped. It was found that the incorporation of Au nanoparticles, about 5–15 nm in diameter, did not disrupt the c-axis orientation of the films. Fortunately, the incorporation of Au nanoparticles decreased the resistivity of Bi2Sr2Co2Oy films while maintained the Seebeck coefficient almost unchanged, thus resulted in an enhanced power factor. Possible mechanisms were proposed to explain the results. This work demonstrated a promising approach to optimize the thermoelectric performance of layered cobaltite thin films. Keywords: Thermoelectric, Layered cobaltite thin films, Au nanoparticles, Pulsed laser deposition

Raman spectroscopy is a practice tool for tissue detection. This work demonstrated that confocal micro-Raman spectroscopy (CMRS) and surface-enhanced Raman spectroscopy (SERS) have promising exploratory potential for the detection of nasopharyngeal carcinoma (NPC) based on nasopharyngeal swab smear.

Reflectance spectroscopy is a low-cost, nondestructive, and noninvasive method for detection of neoplastic lesions of mucosal tissue. This study aims to evaluate the capability of reflectance spectroscopy system under white light (400–700 nm) with a multivariate statistical analysis for distinguishing nasopharyngeal carcinoma (NPC) from nasopharyngeal benignex vivotissues. High quality reflectance spectra were acquired from nasopharyngealex vivotissues belonging to 18 noncancerous and 19 cancerous subjects, and the combination of principal component analysis-linear discriminant analysis (PCA-LDA) along with leave-one-spectrum-out cross-validation (LOOCV) diagnostic algorithm was subsequently employed to classify different types of tissue group, achieving a diagnostic sensitivity of 73.7% and a specificity of 72.2%. Furthermore, in order to distinguish NPC from nasopharyngeal benignex vivotissues based on reflectance spectra simply, spectral intensity ratios of oxyhemoglobin (R540/R576) were used as an indicator of the carcinogenesis associated transformation in the hemoglobin oxygenation. This tentative work demonstrated the potential of reflectance spectroscopy for NPC detection usingex vivotissue and has significant experimental and clinical value for furtherin vivoNPC detection in the future.

This paper aims to understand the fundamental interaction mechanism between molybdenite and kaolinite in gypsum solution using kerosene as collector. Micro-flotation tests were conducted to study the effect of gypsum solution on the flotation performance of mixed &minus, 74 &mu, m molybdenite and &minus, 10 &mu, m kaolinite mineral. The results showed that the recovery of molybdenite decreased from 86% to 74% while the gypsum solution concentration increased from 0 to 800 mg/L, indicating the detrimental effect of kaolinite on molybdenite flotation could be enhanced by gypsum solution. This is mainly caused by the slime coating of kaolinite on molybdenite through dissolved calcium ion of gypsum solution. In order to confirm the slime coating phenomenon, zeta potential distribution, scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurements were used to investigate interaction characteristics and mechanisms. The zeta potential distribution results revealed that mixed samples had the value between signal molybdenite and kaolinite samples in gypsum solution, which proved the coating phenomenon of kaolinite on molybdenite. Moreover, the coating phenomenon was becoming more and more obvious with the gypsum solution concentration. The coating phenomenon of kaolinite on molybdenite surface was also directly observed from SEM results. The AFM results provided further evidence for the possibility of slime coating, as the adhesion force increased with the gypsum solution concentration, which means the aggregates of molybdenite and kaolinite were becoming more stable.

The plug-in hybrid vehicle has been taken as one of the main streams of electric vehicles world wide with the development of battery technology and the remaining obstacles by the fuel cell to be broken through. Fuel cell plug-in vehicle will follow the engine plug-in vehicle because of the more and more strict control of green house gas emission. At this moment, lithium battery is still expensive and safety problem remains. The performance of ultra capacitor has been significantly improved and the price goes down rapidly because of being used on harbor vehicle and mechanical facilities such like container/cargo cranes in-small-batch. It has become a popular ESS for energy regeneration such like the transit buses. The paper will present the advantage and the performance of a FC plug-in hybrid transit bus with ultracapacitors and NiMH batteries. The design and simulation will be covered in the paper.

Current practice for diagnosing nasopharyngeal carcinoma (NPC) is based on invasive tissue biopsy. This study aims to explore the feasibility of using Raman spectroscopy to differentiate cancerous and non-cancerous nasopharyngeal tissue smears, expecting to realize minimal invasive diagnosis using smears from in vivo mucosa tissue by Raman spectroscopy. Biopsy tissue smears were acquired from 74 patients with pathologically diagnosed nasopharyngeal diseases and measured using confocal Raman spectroscopy. Both fingerprint region and high wavenumber Raman spectra were acquired with distinguish features. Multivariate statistical analysis was used to differentiate cancerous and non-cancerous groups, achieving a diagnostic sensitivity of 87.2 and specificity of 85.7 % for differentiating NPC from nasopharyngeal non-cancerous smears. This work indicates that the method has a unique advantage in microanalysis for tissue smears which may provide a promising minimal invasive (or noninvasive) diagnosing tool for cancer diagnosis.

According to the principle of coordinates transform in vector control system and the reduced equation law about motor model, a mathematic model of AC motor is introduced in the MT system, and a simulation model is designed using MATLAB/SIMULINK. The simulation example shows that MATLAB/SIMULINK is an effective simulation tool and the validity of the model is verified as well. As a conclusion, a vector control AC motor has an excellent speed-regulation performance, and is very well competent for working as EV driver.

A drive of EV R&D in China began years ago. The participants have achieved a lot in filed of both whole vehicle and key components. The paper presents the R&D status of electric vehicle in China for reference, which includes pure electric vehicle, hybrid vehicle and fuel cell vehicle as well as the key components such as motor and propulsion system, battery and MEMS and the test base and standards will be also included in the paper.

A computer simulation software named EVSIML has been developed and is being brought to perfection all along. It has combined the MATLAB and Visual C++ programming languages and the Object-Oriented programming technology. The software of EVSIML (Electric Vehicle SIMuLator) is developed by MATALB and Visual C++ (VC) programming languages with Object-Oriented technology on the basis of the drivetrain model of the EV. It makes features of programming of MATALB and Visual C++ with Object-Oriented technology. EVSIML is mainly used to simulate the power performances and fuel economics of EV originally and now its functions have been expanded in order to deal with much computation and analysis about engineering including system match and control analysis. At the same time, as a complicated simulation software, excellent Graphical User Interfaces (GUI), high efficiency, quickly execute speed, good reusability, good maintainability and good expandability are also absolutely necessary. The paper will present the latest improvement on EVSIML and the new features of it in detail. In order to maintain the energy security of China, improve the air quality and enhance the competition of automobile industry of China in the world, the national science ministry of China has especially founded the special important EV project in the national "tenth-five" and "863" program, plan to emphasize particularly on the industrialization of the EV, exert to gain a significant breakthrough in the key cell technology, the system integration technology and the whole vehicle technology of the EV. The EV is a complex system that integrates a number of subsystems such as the vehicle body, electric propulsion, and energy source and energy management. The technologies involved are diversified and multidisciplinary, including electrical and electronic engineering, mechanical and automotive engineering, and chemical engineering. Because of these multidisciplinary and fast-changing EV technologies, the design process of the EV should be flexible, prompt and economical. Computer simulation not only facilitates this design process, but also enhances the system optimisation of the EV.

Micro-Raman spectroscopy is widely used for non-invasive tissue diagnosis and detection, as it provides detailed information about biomolecular composition, structure, and interaction of tissue. In this work, micro-Raman spectroscopy was used to investigate non-cancerous and cancerous nasopharyngeal tissues. The obtained nasopharyngeal tissue samples in vitro are divided into two groups: cancerous (n=12, undifferentiated non-keratinizing carcinomas) and non-cancerous (n=10, 7 chronic inflammations, 2 lymphomas and 1 lymphocytosis). Firstly, we analyzed the Raman spectra in the fingerprint (FP, 400-1800cm-1) region acquired. Preliminary results showed that there are some spectral differences in different pathological conditions. Furthermore, Raman spectra from cancerous and non-cancerous nasopharyngeal tissue in the high wavenumber region (HW, 2800-3100cm-1) were also reported for the first time. After detailed analysis, we achieved significant differences in Raman bands at 2854, 2874, 2934, and 3067cm-1 between cancerous and non-cancerous nasopharyngeal tissues. This study demonstrates that both fingerprint and high wavenumber regions of micro-Raman spectroscopy have the potential for the early detection of nasopharyngeal carcinomas.

The transverse thermoelectric (TE) effect has been investigated in c axis tilted Bi2Sr2Co2Oy thin films with different oxygen content. The film samples were fabricated by a chemical solution deposition method annealed under different atmospheres of O2, air, and N2, respectively. Open-circuit transverse voltage signals were observed when the surface of the films was heated by a pulsed laser as well as a continuous thermal source. With the increase of oxygen content in the films, the amplitude of the observed voltage signals increased while the response time decreased. The experimental results can be explained by a mechanism involving the transverse TE effect as well as the transport theory of TE materials.

The analysis of drive cycle is the basis of vehicular real-control during design and the application of electric vehicles. Beijing will hold the Olympic Games in 2008 and there will be about 1000 electric buses made full use of at that time. The requirements of the electric buses' design according to tested data of two kinds of drive cycles will be analyzed in the paper. And it dictates that the entire considerations of different drive cycles are very important for current electric buses' design and their different requirements of energy and power, which is necessary for E-bus design and the realization of efficient real-time control.

The paper presents an analysis of electric assist control strategy for hybrid electric vehicles and makes an analysis of simulation on advisor platform.

The molecular characterization of ABO blood types, which is clinically significant in blood transfusion, has clinical and anthropological importance. Polymerase chain reaction sequence-based typing (P CR-SBT) is one of the most commonly used methods for the analysis of genetic bases of ABO blood types. However, such methods as PCR-SBT are time-consuming and are high in demand of equipments and manipulative skill. Here we showed that membrane electrophoresis based SERS method employed for studying the molecular bases of ABO blood types can provide rapid- and easy-operation with high sensitivity and specificity. The plasma proteins were firstly purified by membrane electrophoresis and then mixed with silver nanoparticles to perform SERS detection. We use this method to classify different blood types, including blood type A (n=13), blood type B (n=9) and blood type O (n=10). Combination of principal component analysis (PCA) and liner discriminant analysis (LDA) was then performed on the SERS spectra of purified albumin, showing good classification results among different blood types. Our experimental outcomes represent a critical step towards the rapid, convenient and accurate identification of ABO blood types . Keywords: Silver nanoparticles; Surface-enhanced Raman scattering; Membrane electrophoresis; Principal component analysis (PCA); Liner discriminant analysis (LDA)