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The mineral zircon has a robust crystal structure, preserving a wealth of geological information through deep time. Traditionally, trace elements in magmatic and hydrothermal zircon have been employed to distinguish between different primary igneous or metallogenic growth fluids. However, classical approaches based on mineral geochemistry are not only time consuming but often ambiguous due to apparent compositional overlap for different growth environments. Here, we report a compilation of 11 004 zircon trace element measurements from 280 published articles, 7173 from crystals in igneous rocks, and 3831 from ore deposits. Geochemical variables include Hf, Th, U, Y, Ti, Nb, Ta, and the REEs. Igneous rock types include kimberlite, carbonatite, gabbro, basalt, andesite, diorite, granodiorite, dacite, granite, rhyolite, and pegmatite. Ore types include porphyry Cu-Au-Mo, skarntype polymetallic, intrusion-related Au, skarn-type Fe-Cu, and Nb-Ta deposits. We develop Decision Tree, XGBoost, and Random Forest algorithms with this zircon geochemical information to predict lithology or deposit type. The F1-score indicates that the Random Forest algorithm has the best predictive performance for the classification of both lithology and deposit type. The eight most important zircon elements from the igneous rock (Hf, Nb, Ta, Th, U, Eu, Ti, Lu) and ore deposit (Y, Eu, Hf, U, Ce, Ti, Th, Lu) classification models, yielded reliable F1-scores of 0.919 and 0.891, respectively. We present a web page portal (http://60.205.170.161:8001/) for the classifier and employ it to a case study of Archean igneous rocks in Western Australia and ore deposits in Southwest China. The machine learning classifier successfully determines the known primary lithology of the samples, demonstrating significant promise as a classification tool where host rock and ore deposit types are unknown.

Byline: Wu-Qi. Qiu, Ju-Fang. Shi, Lan-Wei. Guo, A-Yan. Mao, Hui-Yao. Huang, Guang-Yu. Hu, Pei. Dong, Fang-Zhou. Bai, Xiao-Ling. Yan, Xian-Zhen. Liao, Guo-Xiang. Liu, Ya-Na. Bai, Jian-Song. Ren, Xiao-Jie. Sun, Xin-Yu. [...]

AbstractThis study aims to investigate the characteristics of night soil/horse manure with leaf co-composting using aerobic static composting method. Two influencing factors, including composting materials and aeration pattern, were investigated by determining the change in the principal physicochemical properties, i.e. temperature, volatile solid, carbon, nitrogen, hydrogen, carbon-to-nitrogen ratio, heavy metals, ammonia nitrogen, nitrate nitrogen, and germination index (GI). The mixture of horse manure and leaf can achieve high composting temperature, long retention time of high temperature (55 °C), fast organic matter degradation, and high GI under the same aeration pattern. Under the same composting materials, the intermittent aeration pattern during composting was superior to the continuous aeration pattern because the former promoted the composting process.

An analytical method for determination of 10 kinds of caine-type prohibited ingredients in cosmetics was developed. The analytes were enriched through supramolecular solvent-based dispersive liquid-liquid microextraction, followed by instrumental analysis with ultra performance liquid chromatography coupled with differential mobility spectrometry-mass spectrometry. The supramolecular solvent was prepared with dodecanol as extraction solvent and tetrahydrofuran as dispersing agent for vortex-assisted dispersive liquid-liquid microextraction for cosmetic samples. Several factors were optimized including the composition and amount of the supramolecular solvent used in sample preparation and vortex time on the extraction efficiency. The separation of isomers by differential mobility spectrometry was systematically investigated. The results showed that the sample could be effectively extracted by 4 mL of supramolecular solvent consisting of dodecanol and tetrahydrofuran with the help of 3 min vortexing. Under the optimized conditions of carrier gas, separation voltage and compensation voltage, the isomers of benzocaine and tricaine could be well separated by differential mobility spectrometry for qualitative and quantitative analysis, which could hardly be chromatographically separated. The 10 kinds of caine-type compounds exhibited good linearity in their respective concentration ranges, with correlation coefficients better than 0.99. The limits of detection and quantitation were in the range of 0.2–8.0 μg kg−1and 0.4–20.0 μg kg−1, respectively. The average recoveries at low, medium and high spiked levels ranged from 70.7% to 94.7% with relative standard deviations from 1.2% to 12.7% (n= 6). The method is simple, rapid, efficient, and is suitable for the simultaneous determination of the 10 kinds of caine-type prohibited ingredients in cosmetics.

As the well-known difficulties are that feedback signals are not easy and economical measurement in practice for active control, this paper presents a study of state estimation for active control of independently rotating wheels (IRW) based on observers. The reduced-order observer and high-order sliding mode observer are used to provide reliable and accurate estimations of the wheel pair state and track curvature using practical sensors. This proposed method uses less sensors than the one of previous studies. Furthermore, lateral accelerator and yaw velocity sensors (gyros) are economical and available for active steering and stability control system to obtain the required feedback signals. The wheels’ relative rotational speed, track curvature and yaw angle of wheelsets are the feedback signals for IRW active control approach. Computer simulations are used to verify the effectiveness of proposed methods and assess control performance in stability and negotiation.

Oil and gas long-distance pipelines which are buried under ground often have to be closely laid in the narrow area with the high voltage electric-power line. The earth electrode of the electric tower seriously impacts the cathodic protection system of the pipeline when it discharges electricity into the earth. Sometimes the cathodic protection system may even lose its efficacy and the pipe being corroded. Under this condition, fiber reinforced plastics (FRP) has been paid more and more attention as the alterative of the steel pipe because of its outstanding cathodic-resisting property. In this article, the property of FRP compared with the steel was analyzed. The advantages and shortcomings of FRP as the material of oil and gas long-distance pipeline were introduced. Furthermore the feasibility of FRP pipeline was discussed.

A single-chamber and membrane-less microbial fuel cells (MFC) was successfully started up using anaerobic sludge as inoculums without any nutrient elements for 20 d. Under 30 °C, excess sludge SS was about 21000 mg·L-1, anode area for 31.4 cm2 and in 200 mM NaCl concentration agent conditions experiment MFC, while the control device (CD) directly with original sludge anaerobic digestion. The electricity generation of microbial fuel cell and the contrast of substrate changes were investigated. The results show that obtained maximum voltage is 597.3 mV, pH in MFC is slightly higher than in contrast test. Volume reduction in MFC is larger than the controls. Reducing sugar in MFC is lower than that in CDs. Proteins increase at first and then decrease, finally there is no significant difference in both of MFC and CD. Key words: Microbial Fuel Cells, Excess Sludge, Anaerobic Digestion, Reutilization

Based on the previous studies, this experiment presented a new kind of microbial fuel cells (MFC), single-chamber air cathode microbial fuel cells without proton membrane. After investigating the contrast of substrate changes in microbial fuel cells and simple anaerobic digestion, the analysis results of soluble chemical oxygen demand (SCOD), TP, TN and NH3-N show that: SCOD increase firstly, then decrease, to the end, descend. As a result, we find that SCOD in MFC is lower than that in control device (CD). Throughout the whole reaction period, TP in MFC is lower than that in CD. TN and NH3-N show upward trend after a reaction period.

Biological nitrogen removal via shortcut nitrification-denitrification is being studied by more and more engineers because of its economical advantages. This paper summarizes the progress of shortcut nitrification-denitrification on high NH4+-N and low carbon source wastewater and low NH4+-N and high carbon source wastewater, and raises the thought that realize shortcut nitrification-denitrification.

Higher nitrogen and phosphorus in the water cause water eutrophication. Nitrogen and phosphorus removal are the primary methods of solving water eutrophication. This paper analyzed the development and key technology from Triple oxidation ditch, UNITANK process to MSBR process for the object of nitrogen and phosphorus removal.

Leachate biochemical effluent containing large quantities of refractory matters are difficult to degrade by traditional biological processes. Photocatalysis technology seems to be a promising solution for leachate biochemical effluent because it can oxidize refractory organic compounds to harmless inorganics. But there are two key problems in TiO2 photocatalytic degradation of biologically treated leachate. One is low quantum yield, the other is low photocatalytic activity in the visible-light region. The advice about solar photocatalytic degradation of biologically treated leachate using transition metal-nonmetal co-doped TiO2 is put forward.

Background: This study examined the significant association between carbamazepine (CBZ)-induced Stevens-Johnson Syndrome (SJS)/toxic epidermal necrolysis (TEN) and HLA-B*15:02in epilepsy patients of Han ethnicity living in northeastern China. Methods: CBZ-SJS/TEN patients and CBZ-tolerant control patients were genotyped for HLA-B*15:02by PCR amplification using sequence-specific primers. Patients then were evaluated for HLAgenotypes using PCR with sequence-based typing. Results: Eight of 35 CBZ-SJS/TEN patients carried HLA-B*15:02(22.9%) versus2 of 125 in CBZ-tolerant control patients (OR = 18.222, 95% CI = 3.662-90.662, p = 0.000). Our results suggest that HLA-B*15:02is necessary but is not sufficient to produce SJS/TEN following CBZ treatment among Han individuals from northeastern China. Other HLAalleles, including A*33:03, B*58:01, C*03:02, DQB1*03:03, and DRB1*07:01may be associated weakly with CBZ-SJS/TEN. Conclusions: Our results are not consistent with previous studies reporting a strong association between HLA-B*15:02and CBZ-SJS/TEN among individuals from southern, southwestern, and central China. Other genes maybemore tightly associated with CBZ-SJS/TEN. Screening for HLA-B*15:02still may be recommended for patients in northeastern China before starting CBZ.

A series of experiments were carried out aiming at resource utilization of fresh green waste and sewage sludge. The green waste, rice straw and sewage sludge were chosen as raw materials and packing materials in composting experiments to study the variation characteristics of composting in different aeration patterns. It was found that the effect of intermittent aeration pattern during composting was better than continuous aeration pattern according to the results of detection of composting temperature, oxygen, carbon dioxide.

As a kind of emerging energy with massive reserves, natural gas hydrates are becoming the hot spot of global research. The elastic properties of gas hydrate bearing sediments (HBS) are the fundamental parameters for gas hydrates exploration and resource evaluations. As the original coring in HBS is difficult and expensive, experimental method is important to study the problem. An acoustic wave in-situ measuring system for HBS was developed. Using the in-situ method, hydrate bearing rock samples of different hydrate saturation were synthesized, of which the supersonic wave measurement was carried out under different confining pressure. According to the elasticity theory, the dynamic elastic parameters were obtained using the measured ultrasonic wave velocity. The results show that compressional and shear waves increase with the confining pressure and hydrate saturation increasing, and so the dynamic elastic modulus is.

The effect of temperature on two stage aged-refuse-based reactor which treats leachate in natural ventilation was investigated in autumn and winter. Results indicate that the average concentrations of COD in treated effluent increase from 726 mg/L in autumn to 2000 mg/L in winter in the first stage reactor while they are 246 mg/L and 1010 mg/L respectively in the second stage reactor. The average concentrations of NH3-N in treated effluent increase from 123.7 mg/L in autumn to 620 mg/L in winter in the first stage reactor while they are 123.7 mg/L and 620 mg/L respectively in the second stage reactor. Accordingly, the average removal rates of COD decrease from 81.7% of autumn to 73% of winter in the first stage reactor and decrease from 64.7% to 52% in the second stage reactor, and finally, the total COD removal rate in this system drops from 92.7% in autumn to 85.8% in winter. So we can conclude that the effect of temperature on the first stage aged refuse reactor is better than that on the second stage aged refuse reactor.

The tread wear would change the wheel/rail relation and seriously affect the railway vehicle dynamic behaviors. After testing the several EMUs under running ,this paper not only analyses the discipline of tread wear, but also computers the influence on wheel/rail contact geometry by a program devopled in Matlab/GUI. A MBS model of trailer of EMUs is constructed, including the model of passagers. The dynamic performance of EMUs and riding comfort are compared among the standard, worn and turned tread profile. We draw the following conclusions：Tread profile after running for a long time without turning would emerge harmful concave worn；The unsymmetrical wheel/rail contact would increame the risk of derailment and debase passengers comfort of EMUs；After turning , the dynamic performance of EMUs can be improved.

Comprehensive health economic evaluation, a key component of the Cancer Screening Program in Urban China (CanSPUC), was expected to support government policy-making on screening initiatives for common cancers (lung, breast, colorectal, oesophageal, liver, and stomach cancer) in urban China. Estimation of expenditure for cancer diagnosis and treatment from a societal perspective was an essential component. The aim of this study was to estimate direct medical and non-medical expenditure and to discern the resultant financial burden.