摘要：The leaching behavior of Tunceli malachite mineral was investigated in nitric acid solutions by two steps to evaluate the effect of various experimental *** the first step,the optimal conditions for the leaching process were determined,while in the second step,a kinetic evaluation for the process was *** the optimization experiments,the concentration of nitric acid,temperature,stirring speed,and solid-to-liquid ratio were selected as the independent variables,and the central composite design method(CCD)was applied to the experimental *** the end of the experiments,the optimal values for the concentration of nitric acid,temperature,solid-to-liquid ratio and stirring speed were determined to be 0.5 mol/L,50℃,0.004 g/m L and 500 r/min,*** the optimal conditions,the leaching rate was found to be 99%for 120 min of reaction *** the kinetic evaluation tests,the effects of the concentration of nitric acid,temperature,stirring speed,solid-to-liquid ratio and particle size on the leaching rate of copper from malachite were *** these tests,it was determined that the leaching rate increased with the increase in the temperature,acid concentration and stirring speed,and with the decrease in the particle size and solid-to-liquid *** consequence of the kinetic analysis,it was observed that the leaching kinetics followed the mixed kinetic model,and a mathematical model for the leaching process was *** activation energy for this process was calculated to be 36.23 k J/mol.

摘要：In order to improve the utilization rate of foam,an arc jet nozzle was designed for precise dust *** theoretical analysis,the different demands of foam were compared amongst arc jets,flat jets and full cone jets when the dust source was covered identically by *** is proved that foam consumption was least when an arc jet was *** production capability of an arc jet nozzle under different conditions was investigated through *** results show that with the gas liquid ratio(GLR)increasing,the spray state of an arc jet nozzle presents successively water jet,foam jet and *** a reasonable working condition range of foam production and a fixed GLR,foam production quantity increases at first,and then decreases with the increase of liquid supply *** the inner diameter of the nozzle is 14 mm,the best GLR is 30 and the optimum liquid supply quantity is0.375 m^3/*** results of field experiments show that the total dust and respirable dust suppression efficiency of arc jet nozzles is 85.8%and 82.6%respectively,which are 1.39 and 1.37 times higher than the full cone nozzles and 1.20 and 1.19 times higher than the fiat nozzles.

摘要：The input/output(I/O)pins of an industry-level fluorescent optical fiber temperature sensor readout circuit need on-chip integrated high-performance electro-static discharge(ESD)protection *** is difficult for the failure level of basic N-type buried layer gate-controlled silicon controlled rectifier(NBL-GCSCR)manufactured by the 0.18µm standard bipolar-CMOS-DMOS(BCD)process to meet this ***,we propose an on-chip integrated novel deep N-well gate-controlled SCR(DNW-GCSCR)with a high failure level to effectively solve the problems based on the same semiconductor *** computer-aided design(TCAD)simulation is used to analyze the device *** are tested by transmission line pulses(TLP)to obtain accurate ESD *** holding voltage(24.03 V)of NBL-GCSCR with the longitudinal bipolar junction transistor(BJT)path is significantly higher than the holding voltage(5.15 V)of DNW-GCSCR with the lateral SCR path of the same ***,the failure current of the NBL-GCSCR device is 1.71 A,and the failure current of the DNW-GCSCR device is 20.99 *** the gate size of DNW-GCSCR is increased from 2µm to 6µm,the holding voltage is increased from 3.50 V to 8.38 *** optimized DNW-GCSCR(6µm)can be stably applied on target readout circuits for on-chip electrostatic discharge protection.

摘要：One of the most serious conundrum facing the stope production in underground metalliferous mining is uneven break （UB： unplanned dilution and ore-loss）. Although the UB has a huge economic fallout to the entire mining process, it is practically unavoidable due to the complex causing mechanism. In this study, the contribution of ten major UB causative parameters ha,; been scrutinised based on a published UB predicting artificial neuron network （ANN） model to put UB under the engineering management. Two typical ANN sensitivity analysis methods, i.e., connection weight algorithm （CWA） and profile method （PM） have been applied. As a result of CWA and PM applications, adjusted Qrate （AQ） revealed as the most influential parameter to UB with contribution of 22,40% in CWA and 20,48% in PM respectively. The findings of this study can be used as an important reference in stope design, production, and reconciliation stages on underground stoping mine.

摘要：The effect of the design parameter on the clutch engagement process of the hydro-mechanical continuously variable transmission(CVT)was ***,the model of the power train was developed with the software of SimulationX,and the clutch shift experiment was used to validate the correctness of the ***,the friction coefficient function was fitted with the test data to get the friction coefficient model suitable for this ***,based on the evaluating index of the friction torque and the friction power,two groups of design parameters(oil pressure and friction coefficient)were simulated and explained the changing regulation *** to the simulation results,the high oil pressure and friction coefficient can reduce the slipping *** large oil pressure can increase the peak torque but the effect of friction coefficient on the peak torque is not so *** friction power reaches the maximum value at 3.2 s,the peak value increases as the oil pressure and friction coefficient *** effect of the oil pressure on the clutch engagement and thermal performance is greater than the friction coefficient.

摘要：Due to their simple structure,crooked plates are widely processed into energy absorption *** are obvious differences in the final deformation of crooked plates with different materials and dynamic conditions under the impact of constant-input kinetic *** better understand this phenomenon,we solved the Zhang-Yu equation with Maple software,obtained the law of generalized coordinates(rotation angle)of the energy absorber changing with time,and compared the energy absorption capacity of a crooked plate energy absorber under different *** better understand how the motion of the energy absorber is affected by the change of parameters,we calculated the phase diagram of the energy absorber *** many numerical simulations,we found that the four-crooked plate energy absorber should have a mass-sensitive *** established the finite element model of dynamic buckling of mild steel and 6061-T6 aluminum alloy,and compared it with the Calladine-English dynamic experiment and Zhang-Yu rigid viscoplastic *** results show that:(1)the Zhang-Yu rigid viscoplastic model has more guiding significance for mild steel(strain rate-sensitive material),and has greater error for 6061-T6 aluminum alloy(strain rate-insensitive material),and the prediction error further increases with the initial angle;and(2)by modifying the equivalent plastic length A of a plastic hinge according to the finite element model,the prediction accuracy of the Zhang-Yu rigid viscoplastic model can be *** research results certain guiding significance for the design and manufacture of energy-absorbing structures of crooked plates.

摘要：The immune response after implantation of a biomaterial may shorten the functional life of the implant,depending on the degree of the *** this study,we used a polyacrylamide-alginate(PAAm-Alg)hydrogel,which has been previously characterized as a biocompatible material and shown to enhance regeneration of cartilage in vivo,along with a graphiteenhanced hydrogel(PAAm-Alg-G)as a non-biocompatible counterpart,to evaluate macrophage attachment and polarization to pro-or anti-inflammatory *** performance of each biomaterial in the presence of fibroblasts and chondrocytes was validated by an in vitro model which demonstrated modulation of the foreign-body response.A blend of 5%gelatin methacryloyl and 0.1%methacrylated hyaluronic acid was optimized to mimic the extracellular matrix(ECM)and support cell viability,proliferation,migration,and functionality at an initial concentration of 3.25×10^(5) cells/*** PAAm-Alg-G hydrogel localized in the simulated ECM showed cytotoxic and genotoxic effects for both fibroblasts and chondrocytes,while exhibiting a proliferative effect on macrophages with elevated immune *** M1/M2 ratio was 0.73 for PAAm-Alg hydrogel but 2.64 for PAAm-Alg-G,leading to significant M1 dominance(p0.05).The interleukin-6(IL-6)concentration secreted in the presence of PAAm-Alg hydrogel(4.58 pg/mL)significantly decreased(p<0.0001)on day 13,while the increase(p<0.0001)in interleukin-10(IL-10)concentration(120.73 pg/mL)confirmed the switch from a pro-inflammatory to an anti-inflammatory *** immune responses by developing a simplistic yet powerful three-dimensional in vitro model provides advantages in preparing for clinical use of biomaterials.

摘要：Aiming at soft rock ground support issues under conditions of high stress and long-term water immersion, the ground failure mechanism is revealed by taking the deep-water sumps of Jiulong Mine as the engineering background and employing field investigation, tests of rock structure, mechanical properties and mineral composition. The main factors leading to the surrounding rock failure include the high and complex stress state of the water sumps, high-clay content and water-weakened rock, and the unreasonable support design. In this paper, the broken and fractured rock mass near roadway opening is considered as ground small-structure, and deep stable rock mass as ground large-structure. A support technology focusing on cutting off the water, strengthening the small structure of the rock and transferring the large structure of the rock is proposed. The proposed support technology of interconnecting the large and small structures, based on high-strength bolts, high-stiffness shotcrete layer plugging water,strengthening the small structure with deep-hole grouting and shallow-hole grouting, highpretensioned cables tensioned twice to make the large and small structures bearing the pressure evenly,channel-steel and high-pretensioned cables are used to control floor heave. The numerical simulation and field test show that this support system can control the rock deformation of the water sumps and provide technical support to similar roadway support designs.

摘要：Rockburst prediction is of vital significance to the design and construction of underground hard rock mines.A rockburst database consisting of 102 case histories,i.e.,1998−2011 period data from 14 hard rock mines was examined for rockburst prediction in burst-prone mines by three tree-based ensemble *** dataset was examined with six widely accepted indices which are:the maximum tangential stress around the excavation boundary(MTS),uniaxial compressive strength(UCS)and uniaxial tensile strength(UTS)of the intact rock,stress concentration factor(SCF),rock brittleness index(BI),and strain energy storage index(EEI).Two boosting(AdaBoost.M1,SAMME)and bagging algorithms with classification trees as baseline classifier on ability to learn rockburst were *** available dataset was randomly divided into training set(2/3 of whole datasets)and testing set(the remaining datasets).Repeated 10-fold cross validation(CV)was applied as the validation method for tuning the *** margin analysis and the variable relative importance were employed to analyze some characteristics of the *** to 10-fold CV,the accuracy analysis of rockburst dataset demonstrated that the best prediction method for the potential of rockburst is bagging when compared to AdaBoost.M1,SAMME algorithms and empirical criteria methods.

摘要：We report the development of a metastasis-on-a-chip platform to model and track hepatocellular carcinoma(HCC)-bone metastasis and to analyze the inhibitory effect of an herb-based compound,thymoquinone(TQ),in hindering the migration of liver cancer cells into the bone *** bioreactor consisted of two chambers,one accommodating encapsulated HepG2 cells and one bone-mimetic niche containing hydroxyapatite(HAp).Above these chambers,amicroporous membrane was placed to resemble the vascular barrier,where medium was circulated over the *** was observed that the liver cancer cells proliferated inside the tumor microtissue and disseminated from the HCC chamber to the circulatory flow and eventually entered the bone *** number of metastatic HepG2 cells to the bone compartment was remarkably higher in the presence of HAp in the *** was then used as ametastasis-controlling agent in both free form and encapsulated nanoparticles,to analyze its suppressing effect on HCC *** indicated that the nanoparticle-encapsulated TQ provided a longer period of inhibitory *** summary,HCC-bone metastasis-on-a-chip platform was demonstrated to model certain key aspects of the cancer metastasis process,hence corroborating the potential of enabling investigations on metastasis-associated biology as well as improved anti-metastatic drug screening.