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The 2021 Yangbi Ms 6.4 earthquake in Yunnan, China, occurred in an area where the Global Positioning System (GPS) geodetic observations are particularly intensive. Based on a detailed retrospective analysis of the GPS observations of about 133 stations distributed in the proximately 400 km × 400 km region that contains the area affected by the earthquake., we obtain a high-resolution GPS velocity field and strain rate field and then derive the present-day slip rates of major faults in the region with the commonly used half-space elastic dislocation model and constraints from the GPS velocity field. Furthermore, by calculating the seismic moment accumulation and release and deficit rates in the main fault segments and combining with the distribution characteristics of small earthquakes, we evaluate the regional seismic risk. The results show that (1) there was a localized prominent strain accumulation rate around the seismogenic area of the impending Yangbi Ms 6.4 earthquake, although this was not the only area with a prominent strain rate in the whole region. (2) The seismogenic area of the earthquake was just located where the strain direction was deflected, which, together with the localized outstanding maximum shear strain and dilatation rates, provides us with important hints to determine the potential areas of future strong earthquakes. (3) Of all the seismogenic fault segments with relatively high potentials, judged using the elapsed time of historical earthquakes and effective strain accumulation rate, the middle section of the Weixi–Qiaohou fault has a higher earthquake risk than the southern section, the Midu–Binchuan section of the Chenghai fault has a higher risk than the Yongsheng section and the Jianchuan section of the Jianchuan–Qiaohou–Lijiang–Xiaojinhe fault has a higher risk than the Lijiang section.

N-acetylneuraminic acid (Neu5Ac) is a functional metabolite and has been demonstrated to be a risk factor for cardiovascular diseases. It is not clear whether Neu5Ac is associated with a higher risk of cerebrovascular disorders, especially moyamoya disease (MMD). We sought to elucidate the association between serum Neu5Ac levels and MMD in a case–control study and to create a clinical risk model. In our study, we included 360 MMD patients and 89 matched healthy controls (HCs). We collected the participants’ clinical characteristics, laboratory results, and serum Neu5Ac levels. Increased level of serum Neu5Ac was observed in the MMD patients (p = 0.001). After adjusting for traditional confounders, the risk of MMD (odds ratio [OR]: 1.395; 95% confidence interval [CI]: 1.141–1.706) increased with each increment in Neu5Ac level (per μmol/L). The area under the curve (AUC) values of the receiver operating characteristic (ROC) curves of the basic model plus Neu5Ac binary outcomes, Neu5Ac quartiles, and continuous Neu5Ac are 0.869, 0.863, and 0.873, respectively. Furthermore, including Neu5Ac in the model offers a substantial improvement in the risk reclassification and discrimination of MMD and its subtypes. A higher level of Neu5Ac was found to be associated with an increased risk of MMD and its clinical subtypes.

Magnetic Particle Imaging (MPI) is an emerging medical imaging modality based on the non-linear response of superparamagnetic iron oxide nanoparticles (SPIONs), and imaging the concentration of the SPIONs. At present, MPI reconstruction mainly includes x-space and system matrix methods. The x-space method has an extremely fast reconstruction speed and the final reconstructed image can be seen as the result of convolution of particle distribution with point spread function (PSF), but it causes anisotropic resolution and artifacts due to the effect of anisotropic PSF. In this work, we propose a hybrid approach that combines the x-space and model-based system matrix methods to remove the PSF blur and reconstruct the isotropic resolution and artifact removal MPI images. We first build the system matrix in the time domain transformed by the ideal MPI scan model in the time domain. Then, we convert the x-space reconstruction process into a matrix operation, and subsequently combine several matrices into a system matrix (forward model). The input of this forward model is particle distribution and the output is the x-space reconstructed image, which is affected by the PSF blurring. The PSF blur removal is then converted to an inverse problem solving, which we implement using the Kaczmarz method to obtain isotropic resolution and artifact removal images. The results of simulation and phantom experiments demonstrate that our method could achieve the best isotropic resolution and image quality comparing with the standard x-space method and other PSF removal methods., International Journal on Magnetic Particle Imaging IJMPI, Vol 9 No 1 Suppl 1 (2023)

Under the influence of novel corona virus pneumonia, the staff are controlled. Therefore, it is a difficult problem to measure the parameters of wood structure building on site. The measurement error of traditional wood structure parameters in complex environment is large, so an efficient and accurate measurement and recognition method is needed. In this paper, a method combining random decrement method and ITD method is proposed to measure the frequency, damping ratio and other structural dynamic parameters of ancient building timber structure under crowd random load excitation. In this paper, the frequency and damping ratio of the typical ancient building timber structure are predicted by using the artificial neural network model trained by the known data. The experimental results show that the population density has a great influence on the measurement of the dynamic parameters of the wooden structure of ancient buildings. Using this method, combined with the long-term monitoring data of temperature and humidity, the influence of various environmental factors on the dynamic characteristics of the structure can be analyzed. This provides data support for structural damage identification and health monitoring.

In the summer of 2018, a comprehensive field campaign, with measurements on HONO and related parameters, was conducted at the foot (150 m a.s.l.) and the summit of Mt. Tai (1534 m a.s.l.) in the central North China Plain (NCP). With the implementation of a 0-D box model, the HONO budget with six additional sources and its role in radical chemistry at the foot station were explored. We found that the model default source, NO + OH, could only reproduce 13 % of the observed HONO, leading to a strong unknown source strength of up to 3 ppbv h−1. Among the additional sources, the NO2 uptake on the ground surface dominated (∼ 70 %) nighttime HONO formation, and its photo-enhanced reaction dominated (∼ 80 %) daytime HONO formation. Their contributions were sensitive to the mixing layer height (MLH) used for the parameterizations, highlighting the importance of a reasonable MLH for exploring ground-level HONO formation in 0-D models and the necessity of gradient measurements. A ΔHONO/ΔNOx ratio of 0.7 % for direct emissions from vehicle exhaust was inferred, and a new method to quantify its contribution to the observations was proposed and discussed. Aerosol-derived sources, including the NO2 uptake on the aerosol surface and the particulate nitrate photolysis, did not lead to significant HONO formation, with their contributions lower than NO + OH. HONO photolysis in the early morning initialized the daytime photochemistry at the foot station. It was also a substantial radical source throughout the daytime, with contributions higher than O3 photolysis to OH initiation. Moreover, we found that OH dominated the atmospheric oxidizing capacity in the daytime, while modeled NO3 appeared to be significant at night. Peaks of modeled NO3 time series and average diurnal variation reached 22 and 9 pptv, respectively. NO3-induced reactions contribute 18 % of nitrate formation potential (P(HNO3)) and 11 % of the isoprene (C5H8) oxidation throughout the whole day. At night, NO3 chemistry led to 51 % and 44 % of P(HNO3) or the C5H8 oxidation, respectively, implying that NO3 chemistry could significantly affect nighttime secondary organic and inorganic aerosol formation in this high-O3 region. Considering the severe O3 pollution in the NCP and the very limited NO3 measurements, we suggest that besides direct measurements of HOx and primary HOx precursors (O3, HONO, alkenes, etc.), NO3 measurements should be conducted to understand the atmospheric oxidizing capacity and air pollution formation in this and similar regions.

In the present study, a combined process of microwave-assisted chlorination roasting-water leaching was developed to efficiently extract metal ions from spent ternary lithium-ion batteries. Polyvinyl chloride (PVC) was used as chlorine source to generate HCl for chlorination reaction. Activated carbon was first selected as the optimal absorbing medium material. Subsequently, spent anode graphite was used to induce carbonisation reduction reaction with spent LiNixCoyMnzO2 (NCM) to promote recovery of valuable metals. The characterisations of X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and thermodynamic analysis indicated that HCl derived from PVC pyrolysis could spontaneously react with carbonisation reduction products from spent NCM to form the corresponding water-soluble metal chloride for the effective recovery of valuable metals. Under the optimal conditions with reaction temperature at 450°C, material mass ratio PVC:NCM of 4:1, reaction time at 60 min and microwave power at 500 W, 96.43% of Li, 95.51% of Ni, 95.27% of Co and 95.43% of Mn can be recovered, respectively. The leaching kinetics can be described by the Avrami equation with surface chemical reaction controlled, and the leaching activation energies of Li, Ni, Co and Mn were 36.32, 42.31, 38.84 and 41.96 kJ∙mol−1, respectively. This microwave-assisted method might provide a new route for the effective recycling of spent lithium-ion batteries by chlorinated metallurgical processes.

Chemical and mechanical thinning processes have long been used in stone and pome fruit production. During the thinning of apple flowers, growers use chemicals to regulate the tree load. Hand thinning is applied after the June drop to prune trees with excess crop load. The process of thinning can be unpredictable especially in biennial bearing cultivars. Thus, incentives to optimise chemical usage and to reduce expensive manual labour is ever increasing. Ground based machine vision systems have grown in popularity in orchard management due to the level of detail as well as plant coverage they can inspect with. Additionally, unmanned aerial vehicles (UAV) -based remote sensing technology is becoming a popular non-invasive quality inspection solution. This work proposes a framework for combining UAV and ground based RGB image data to detect flowering intensity in a Dutch Elstar apple orchard. The framework, based on point cloud reconstruction, presents automatic point cloud handling techniques as well as automated unsupervised flowering intensity estimation methods. Two linear regression models based on unsupervised machine learning methods were trained and validated from the framework that estimate flowering intensity in the orchard with both models having R2 > 0.65, RRMSE < 20% and p-stat < 0.005 for the correlation between the image derived flower index and the flower cluster number counted in field. The proposed methods provide a novel strategy for guiding flower thinning using simple RGB images and location data only. Moreover, the proposed methods also reveal the flexibility of intra-tree inspection by checking its sub-volumes.

Supplement 1

In a social context, customer participation in the innovation process is often accompanied by social exclusion situations, which are generally believed to have a negative impact on individuals. However, research results and marketing practices show that social exclusion can also exert a positive influence on creativity, product selection, perceived risk, and so on. Through two experimental studies, this research explores the relationship between social exclusion and customer participation in innovation. It finds that social exclusion has a positive influence on customer participation in innovation and that customer-company identification mediates this relationship.

Nitryl chloride (ClNO2) is an important chlorine reservoir in the atmosphere that affects the oxidation of volatile organic compounds (VOCs) and the production of ROx radicals and ozone (O3). This study presents measurements of ClNO2 and related compounds at urban, polluted rural, and polluted lower tropospheric (mountaintop) sites in the winter of 2017–2018 over the North China Plain (NCP). The nocturnal concentrations of ClNO2 were lower at the urban and polluted rural sites but higher at the polluted lower tropospheric site. The winter concentrations of ClNO2 were generally lower than the summer concentrations that were previously observed at these sites, which was due to the lower nitrate radical (NO3) production rate (P(NO3)) and the smaller N2O5 uptake coefficients (γ(N2O5)) in winter, despite the higher ratios of dinitrogen pentoxide (N2O5) to NO3 in winter. Significant daytime peaks of ClNO2 were observed at all the sites during the winter campaigns, with ClNO2 mixing ratios of up to 1.3 ppbv. Vertical transport of ClNO2 from the residual layers and prolonged photochemical lifetime of ClNO2 in winter may explain the elevated daytime concentrations. The daytime-averaged chlorine radical (Cl) production rates (P(Cl)) from the daytime ClNO2 were 0.17, 0.11, and 0.12 ppbv h−1 at the polluted rural, urban, and polluted lower tropospheric sites, respectively, which were approximately 3–4 times higher than the campaign-averaged conditions. Box model calculations showed that the Cl atoms liberated during the daytime peaks of ClNO2 increased the ROx levels by up to 27 %–37 % and increased the daily O3 productions by up to 13 %–18 %. Our results provide new insights into the ClNO2 processes in the lower troposphere impacted by fresh and intense anthropogenic emissions and reveal that ClNO2 can be an important daytime source of Cl radicals under certain conditions in winter.

In the summer of 2018, a comprehensive field campaign, with measurements on HONO and related parameters, was conducted at the foot (150 m a.s.l.) and the summit of Mt. Tai (1534 m a.s.l.) in the central North China Plain (NCP). With the implementation of a 0-D box model, the HONO budget with six additional sources and its role in radical chemistry at the foot station were explored. We found that the model default source, NO + OH, could only reproduce the observed HONO by 13 %, leading to a strong unknown source strength up to 3 ppbv h−1. Among the additional sources, the NO2 uptake on the ground surface dominated (~70 %) night-time HONO formation, and its photo-enhanced reaction dominated (~80 %) daytime HONO formation. Their contributions were sensitive to the mixing layer height (MLH) used for the parameterizations, highlighting the importance of a reasonable MLH for exploring ground-level HONO formation in 0-D models and the necessity of gradient measurements. A HONO / NOx ratio of 0.7 % for the direct emission was inferred and a new method to quantify its contribution to the observations was proposed and discussed. Aerosol-derived sources, including the NO2 uptake on the aerosol surface and the particulate nitrate photolysis, did not lead to significant HONO formation, with their contributions lower than NO + OH. HONO photolysis in the early morning initialized the daytime photochemistry at both the foot and the summit stations and also was a substantial radical source throughout the daytime, with contributions higher than or about one-quarter of O3 photolysis to OH initiation at the foot and the summit stations, respectively. Moreover, we found that OH dominated the atmospheric oxidizing capacity in the daytime, while NO3 appeared to be significant at night. Peaks of NO3 time series and diurnal variation reached 22 and 9 pptv, respectively. NO3 induced reactions contribute 18 % of nitrate formation potential (P(HNO3)) and 11 % of the isoprene (C5H8) oxidation throughout the whole day. At night, NO3 chemistry led to 51 % or 44 % of P(HNO3) or the C5H8 oxidation, respectively. NO3 chemistry may significantly affect night-time secondary organic and inorganic aerosol formation in this high-O3 region, implying that NO3 chemistry could significantly affect night-time secondary organic and inorganic aerosol formation in this high-O3 region. Considering the severe O3 pollution in the NCP and the very limited NO3 measurements, we suggest that besides direct measurements of HOx and primary HOx precursors (O3, HONO, alkenes, etc.), NO3 measurements should be conducted to understand the atmospheric oxidizing capacity and air pollution formation in this and similar regions.

Nitryl chloride (ClNO2) is an important chlorine reservoir in the atmosphere that affects the oxidation of volatile organic compounds (VOCs) and the production of ROx radicals and ozone (O3). This study presents measurements of ClNO2 and related compounds at urban, rural, and mountain sites in the winter of 2017–2018 over the North China Plain (NCP). The nocturnal concentrations of ClNO2 were lower at the urban and rural sites but higher at the mountain site. The winter concentrations of ClNO2 were generally lower than the summer concentrations that were previously observed at these sites, which was due to the lower nitrate radical (NO3) production rate (P(NO3) and the smaller N2O5 uptake coefficients (γ(N2O5)) in winter, despite the higher dinitrogen pentoxide (N2O5) to NO3 ratios in winter. Significant daytime peaks of ClNO2 were observed at all the sites during the winter campaigns, with ClNO2 mixing ratios of up to 1.3 ppbv. Vertical transport of ClNO2 from the residual layers and prolonged photochemical lifetime of ClNO2 in winter may explain the elevated daytime concentrations. The daytime-averaged chlorine radical (Cl) production rates (P(Cl)) from the daytime ClNO2 were 0.17, 0.11, and 0.12 ppbv h−1 at the rural, urban, and mountain sites, respectively, which were approximately 3–4 times higher than the campaign-averaged conditions. Box model calculations showed that the Cl atoms liberated during the daytime peaks of ClNO2 increased the ROx levels by up to 27–37 % and increased the daily O3 productions by up to 13–18 %.

Atmospheric hydrogen peroxide at the foot and summit of Mt. Tai: variations, sources and sinks, and implications for ozone formation chemistry&nbsp

The BFS algorithm is a basic graph data processing algorithm and many other graph data processing algorithms have similar architectural features with BFS algorithm and can be built on the basis of BFS algorithm model. We analyze the differences between graph algorithms and traditional high-performance algorithms in detail, propose a new way of classifying algorithms into data independent algorithm and data correlation algorithm based on their run-time correlation with data, and use this new classification to explain the validity of the methods proposed in this paper. Through a deeper analysis of graph data, we propose a new fundamental perspective on understanding graph data, establishing a link between two basic data structures, graph and tree, and viewing graph data as consisting of smaller subgraphs and edge trees. Small degree vertices are found to be one of important cause of random memory access. Based on this, we propose a general, easy to implement, and efficient method for graph data processing, with the basic idea of treating low-degree vertices and core subgraphs separately, thus significantly reducing the size of random memory access and improving the efficiency of memory access. Finally, we evaluated the performance of the method on three major data center computing platforms (Intel, AMD, and ARM), and the experiments showed that it brought 19.7%, 31.8% and 17.9% performance improvement, respectively, with a performance-power ratio of 282.70 MTEPS/s on the ARM platform, ranking it among the Green graph500 in November 2019. World No. 1 on the big dataset list., Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible

Aim: Methotrexate (Mtx) is prescribed to reduce pain and inflammation in arthritis patients; however, improved repair and mobility of joints still are the major concerns. Magnesium oil (MO)...

Isolongifolanone is a high value-added sustainable natural product. Recent studies have demonstrated that isolongifolanone possesses anticancer activities. In this study, a series of novel pyrazole ring-containing isolongifolanone derivatives was designed, synthesized, and their anti-proliferative activities in three cancer cell lines were evaluated. Among them, compound 3b exhibited strongest antiproliferative ability on MCF-7 cancer cells and induced the generation of intracellular ROS and mitochondrial depolarization. More importantly, compound 3b still maintained antitumor activity in MCF-7 3D culture systems. The study on molecular mechanism suggested that compound 3b induced apoptosis via activation of caspase-3 and PARP, also via decreasing of Bcl-2 and increasing of Bax and p53. Moreover, compound 3b down-regulated the level of CDK2, a crucial cyclin-dependent kinase which is necessary for the progression of the cells out of the G1 phase of the cell cycle. Docking results showed that compound 3b could bind well with CDK2 by forming hydrogen bonds with amino acid residues (LYS89 and HIS84). These results suggested that compound 3b could be taken as a lead compound for anticancer agents.

In order to improve the flutter stability of a certain type fabricated steel truss bridge, a method of setting guiding plates is proposed. Based on the two-dimensional 3 DOF coupling flutter method (2d-3DOF method), and by use of the numerical wind tunnel established by computational fluid dynamics (CFD), the flutter stability control measures of setting guiding plates are simulated. Through CFD numerical simulation, the flow field characteristics, flutter derivatives and critical flutter speed of original and guiding-plated models are obtained. It is found that for a certain type fabricated steel truss bridge, the guiding plates can improve its flutter stability. Thus, the feasibility and reliability of setting the guiding plates are proved, and the foundation for its further application in practical projects is laid.

With the rapid development of computer technology, the scale of graph increases explosively and large-scale graph computing has been the focus in recent years. Breadth-First Search (BFS) is one of the most important kernels in graph computing. It is the main kernel of the Graph500 benchmark that evaluates the performance of supercomputers and servers in terms of data-intensive applications. In this paper, we implement a highly efficient parallel BFS on CPU-based single-node systems. We propose two algorithm optimization techniques: round-robin vertex shuffle and jumping access. The former can improve the load balance for parallel implementation, while the latter can reduce unnecessary data accesses in the bottom-up algorithm. Our new implementation demonstrates strong scalability and achieves 65.2 GTEPS for Kronecker graph with 2^30 vertices and 2^34 edges on a 4-way Xeon server. The speedup is nearly 12.8 times faster than the original direction-optimizing algorithm. In terms of energy efficiency, the result on our self-designed ARM server is 254.6 MTEPS/W and is superior to conventional x86 server. To our best knowledge, this is the first work that evaluates BFS performance on ARM server and ARM server is suitable for data-intensive applications such as large-scale graph processing.

The electronic industry is highly developed in China, large amounts of wastewater that contains heavy metals is always produced, and heavy metals are transferred into sludge after the water treatment. In recent years, the efficient and harmless treatment of sludge has received much more attention, especially for electronic waste sludge. Considering the need for environmental protection and resource recovery, this chapter explores the bioleaching method for extracting heavy metals from electronic waste sludge. First, the sources of different electronic waste sludge and the species and content of heavy metals in the electronic waste sludge were analyzed. Second, the species of microorganisms that were selected to do the bioleaching process were introduced, and Acidithiobacillus ferrooxidans was chosen to bioleach heavy metals from electronic waste sludge. The optimized conditions, bioleaching mechanisms, and effects were also discussed subsequently. Through the investigation of this chapter, it is important for safe disposal of the electronic waste sludge.

Non-metallic material of waste printed circuit boards (WPCBs) is complicated, which is one of the challenges of electronic waste disposal. Firstly, the source of WPCBs, non-metallic material composition, current major disposal and potential dangers are analyzed in the research. The progress of recycling and disposal technology for non-mentallic materials from waste printed circuit board are summarized on the basis of the physical processing technology, pyrolysis processing and chemical processing technology. Future research is also suggested in the paper. Results obtained can provide a reference for the industrial development of regeneration and reuse of WPCBs nonmetallic materials.

Toll-like receptor (TLR) agonists are known for their ability to inhibit tumor progression via enhancing antitumor cytokines production and cytotoxic T lymphocyte (CTL) activity. Recombinant Helicobacter pylori neutrophil-activating protein fused with maltose-binding protein (rMBP-NAP) has been reported as a novel TLR agonist for antitumor treatment in murine models. The present study aimed to determine the potential and efficacy of the rMBP-NAP for antitumor treatment prior to further clinical trials. The rMBP-NAP was expressed and purified for subsequent experiments. Peripheral blood mononuclear cells (PBMCs) from health donors and patients with lung cancer (LC) were incubated with PBS and 0.2 mg/ml rMBP-NAP. Antitumor cytokines production was assayed using ELISA and reverse transcription-quantitative polymerase chain reaction analysis. The cytolytic activity of PBMCs and the number of Interferon-γ (IFN-γ)-secreting cells were assayed using lactate dehydrogenase and Enzyme-linked ImmunoSpot assays, respectively. The results from the present study revealed that the expression of IFN-γ, interleukin (IL)-2, tumor necrosis factor-α and IL-12 of PBMCs from patients with LC and healthy donors were significantly increased following treatment with rMBP-NAP (P

Various wastes containing zinc and lead are generated in industries such as galvanizing, casting, scrap recycling, smelting, and pyrometallurgical and hydrometallurgical process, as forms of dust, tailings, residues, sludge, and lower-grade lean ores. The disposals of these wastes are now becoming expensive due to the need for the treatment to render the wastes nonhazardous. The options currently available can be comprehensively classified as security landfilling and pyrometallurgical and hydrometallurgical processes. As the wastes containing zinc and lead have been classified as hazardous, conventional landfilling processes should be modified to security landfilling in order to meet the environmental constraints required for the hazardous. The pyrometallurgical processes to treat hazardous wastes containing zinc and lead include Inred, Wala Kiln, Plasma, etc., in which zinc and lead can be easily extracted due to the high temperature used, though a large amount of energy will be consumed and serious secondary pollutions arise. The hydrometallurgical treatment method for wastes containing zinc and lead is by dissolution in mineral acids and alkaline solutions. For acidic leaching process, though zinc and lead will be dissolved to an acceptable high level, the bulk materials, iron, calcium, etc., will also be dissolved completely, and the dissolved iron and other elements have to be precipitated from the leach solutions, possibly leading to the generation of new hazardous wastes and wastewaters. Moreover, a big fraction of zinc exists as zinc ferrites in the dust, which cannot be attacked effectively by acidic leaching processes. Therefore, the acidic leaching process seems not to be economically viable for the treatment of dust. The alkaline process is considered to be a cleaner technology for extracting zinc and lead from the hazardous waste bearing zinc and lead and will be fully introduced in this book.

Black phosphorus (BP) has emerged as a promising material candidate for next generation electronic and optoelectronic devices due to its high mobility, tunable band gap and highly anisotropic properties. In this work, polarization resolved ultrafast mid-infrared transient reflection spectroscopy measurements are performed to study the dynamical anisotropic optical properties of BP under magnetic fields up to 9 T. The relaxation dynamics of photoexcited carrier is found to be insensitive to the applied magnetic field due to the broadening of the Landau levels and large effective mass of carriers. While the anisotropic optical response of BP decreases with increasing magnetic field, its enhancement due to the excitation of hot carriers is similar to that without magnetic field. These experimental results can be well interpreted by the magneto-optical conductivity of the Landau levels of BP thin film, based on an effective k*p Hamiltonian and linear response theory. These findings suggest attractive possibilities of multi-dimensional controls of anisotropic response (AR) of BP with light, electric and magnetic field, which further introduces BP to the fantastic magnetic field sensitive applications.

Low-grade smithsonite ores are leached using alkaline leaching solution. The zinc and lead concentrates can be obtained from lean oxidized zinc ores by alkaline leaching followed by two-step sulfide precipitation of lead and zinc sulfides. It is found that over 85% of both Zn and Pb and less than 10% of Al can be leached from the ore when the leaching operation is conducted at over 95 °C using 5 M NaOH solution as leaching agent. The dissolution of impurities such as Fe, Ca, etc. is negligible. Leaching of Pb can be improved remarkably with addition of NaCl to the leaching systems. Optimum conditions of lead precipitation are found to be 1.8 Na2S/Pb weight ratio, 90 °C, 60 min, and those for zinc precipitation are 2.4 Na2S/Zn weight ratio, 90 °C, 180 min. According to scale-up experiment, total extractions of both lead and zinc reach above 80% from the ores, and the quality of lead and zinc concentrates can meet industrial requirements for roasting process. The Pb-free solution is then used for the electrolysis of metallic Zn using stainless steel electrodes. Zn metal powder with purity higher than 99.5% is obtained. The specific energy for the Zn electrolysis in alkaline leach solution is around 2.4–2.6 kWh/kg Zn, which is lower than the energy consumption of 3.3 kWh/kg Zn required in the conventional process of Zn electrolysis in acidic sulfate electrolytes.

The leaching reaction kinetics of waste bearing zinc and lead are studied. For waste bearing zinc, plot of 1 − (1 − η)1/3 versus leaching time giving linear relationship indicates that the velocity of leaching is controlled by the chemical reaction step; the apparent activation energy is obtained to be 49.22 kJ/mol from an Arrhenius plot. For smithsonite and willemite, during the early stage of leaching reaction, 1 − (2/3)η − (1 − η)2/3 is linear with leaching time, with the apparent activation energy of 19.95 kJ/mol and 19.32 kJ/mol, respectively. In the later stage, 1 − (1 − η)1/3 is linear with leaching time, with the apparent activation energy of 46.54 kJ/mol and 32.64 kJ/mol, respectively. Thus, it indicates that the leaching mechanism of smithsonite changes from inner diffusion control to chemical reaction control and that of willemite changes from inner diffusion control to mixed control, during the leaching process in alkaline solution. The leaching of lead oxide may be controlled by diffusion of NaOH solution passing through the solid-phase layer at lower temperature and less NaOH concentration and by surface chemical reaction at high temperature and high NaOH concentration.

An integrated process consisted of raw materials milling and grinding, leaching, purification, electrowinning, regeneration of the spent electrolytes, vacuum drying, analysis, etc. is developed, and the industrial application flow sheet is designed, with annual yield 1500–2000 tons metallic zinc powder. The process developed has been successfully applied at several plants with a scale of 1000, 1500, and 2000 tons of metallic zinc powder annually. The long-term industrial operations have been shown that the process can use any raw materials containing Cl, F, Si, Fe, As, Cu, etc. The total Zn content of zinc powder produced is over 98% and the metallic zinc content over 94%, which reaches the Class 2 of the national standards of zinc powder quality. Hence, the process is quite different to the acidic process and can apply the raw materials unacceptable for the acidic process. The life cycle assessment method is used to investigate the environmental impacts of the new alkaline processes of production of Zn powder. The results indicate that the environmental impacts of alkaline leaching-electrowinning technology are less than the conventional acid leaching hydrometallurgical processes and pyrometallurgical processes. The energy consumption, greenhouse effect, and acidification in the new processes are 87.76%, 47.80%, and 0.08% of those in the conventional acid leaching hydrometallurgical processes and are 93.94%, 9.25%, and 0.14% of those in the pyrometallurgical processes.

Electrowinning of zinc and lead from alkaline solutions depends on zinc or lead concentrations, temperature, current density, NaOH concentration, electrode distance and electrode material on current efficiency, and energy consumption of zinc or lead electrowinning. The optimum conditions for zinc electrowinning are zinc concentration 30–40 g/L, current density 800–1000 A/m2, NaOH concentration 180–200 g/L, and temperature 30–50 °C, and those for lead electrowinning are lead concentration 20 g/L, 5 g/L lead concentration left in the spent electrolyte, below 50 °C, 400 A/m2 current density, 5 mol/L NaOH concentration, and stainless steel of electrode material. Impurities ions have great effect on the quality of the metallic zinc or lead powder in alkaline leaching electrowinning process. The electrolysis deteriorates when the concentration of arsenide is over 500 mg/L, but \( {\mathrm{CO}}_3^{2-} \), \( {\mathrm{SO}}_4^{2-} \), \( {\mathrm{SiO}}_3^{2-} \), and F- have no effects on zinc electrowinning. Copper will be electrodeposited prior to lead in the cathode. Tin, \( {\mathrm{C}}_4{\mathrm{H}}_4{\mathrm{O}}_6^{2-} \), \( {\mathrm{CO}}_4^{2-} \), and gluten in the solution decrease the current efficiency of the lead electrowinning process, while As, Sb, and W, as well as \( {\mathrm{SO}}_4^{2-} \), \( {\mathrm{PO}}_4^{3-} \), \( {\mathrm{SO}}_3^{2-} \), \( {\mathrm{SiO}}_3^{2-} \), SCN−, \( {\mathrm{CO}}_3^{2-} \), Cl−, and AC−, have no effects.

The impurities in the electrowinning solution can be accumulated during the cycle of alkaline solutions. The integrated process of regeneration and purification of spent electrolyte by causticization is developed. The addition of solid NaOH can be used to separate Na2CO3 in the spent electrolyte. The Na2CO3 is causticized using CaO to regenerate NaOH. During this separation and causticization process, the impurity ions in the spent electrolyte are removed simultaneously. The causticized alkaline solution is recycled to the next leaching step. Moreover, Mo, W, Nb, Ta, etc., will be also dissolved in alkaline solution under the leaching conditions of zinc and lead hazardous wastes. The Mo and W can be recovered with ion flotation and adsorbing colloid flotation process using primary amine dodecylamine (RNH2) as collector and ferric ions or magnesium chloride as co-precipitants or depressant (modifier). Adsorbing colloid flotation (ACF) and ion flotation (IF) using ferric ions as the co-precipitant or sorbent and sodium dodecyl sulfate as the collector can be used for the effective removal of arsenic and molybdenum from aqueous solution. The synergistic extraction of phosphorus, arsenic, and silica from tungstate and molybdate solutions with primary amines and TBP can be realized. Mixed solutions of 12-molybdophosphoric acid and its reduced molybdenum blue solutions are found to be an effective scrubbing process for the combined removal of H2S, SO2, and NOx from gas streams. When the molar ratio of NO2/(SO2 + H2S) in the waste gases is just equal to 1/2, H2S, SO2, and NOx will be removed quantitatively, while the regeneration of scrubbing solution is not needed. H2S and SO2 react with molybdophosphoric acid solution to form elemental sulfur and H2SO4, respectively, while molybdophosphoric acid is reduced into blue species, molybdenum blue solution. The reactions of H2S are rather quickly, while those of SO2 are much more slowly. The resulting molybdenum blue solution is used further for the removal of NOx, in which molybdenum blue is rapidly oxidized back into molybdophosphoric acid and NOx is reduced into N2. Porous white tungstic acid (white tungstic acid), whose composition is firstly revealed in this work, is used to produce new tungstoniobates and tungstotantalates and a series of heteropoly compounds. Moreover, a quick determination method of tungsten concentration is proposed according to the quantitative relationship between the precipitate of white tungstic acid and pH value of a certain range.

Zinc and lead are usually concomitantly present in zinc and lead hazardous wastes such as electric arc furnace (EAF) dust. The selective and quantitative separation of lead from zinc is an important step in these alkaline hydrometallurgy processes. The separation of lead from zinc in alkaline zinc solution, in leaching solutions of zinc and lead hazardous wastes, can be achieved by sodium sulfide precipitation. When the weight ratio of sodium sulfide (average molecular weight 222) added to the lead present in alkaline solution is over 1.8–2.0 (molar ratio approximately 1.5–1.7), lead could be separated selectively and quantitatively, while the zinc remained in the solution without concomitant loss. The residues from the precipitation step are identified as mixtures of PbS and Na2Pb(OH)2S, with PbS being the predominant compound. Sn can be cemented quantitatively from alkaline zinc solution by the addition of zinc powder at 95 °C, 500 rpm with Zn/Sn molar ratio 6. Al in the leaching solution can be removed by Na2SiO3, As can be removed by Fe2(SO4)3 at low NaOH concentration, Cl− can be removed by increasing NaOH content, and Cu can be removed from alkaline lead leaching solution by Pb power replacement.

ZnO, ZnCO3, and Zn2SiO4 are the predominant mineralogical phases in solid wastes bearing zinc. ZnO, ZnCO3, PbO, PbCO3, and PbSO4 can be easily dissolved directly by strong alkaline solutions. However, quite a big portion of zinc in the dust exists as zinc ferrites or zinc sulfide and lead as lead sulfide which cannot be dissolved completely in alkaline solution. Integrated hydrometallurgical processes for leaching the zinc and lead from zinc ferrites, zinc sulfide, and lead as lead sulfide in alkaline medium are developed. For zinc ferrites in EAF dust, the zinc is extracted by direct leaching-melting-leaching of melt or hydrolysis-melting-leaching processes. For the zinc sulfide in solid wastes, the leaching rate of zinc in alkaline solution is improved via chemical conversion with PbCO3 so that the zinc in zinc sulfide can be extracted in NaOH solution with lead carbonate as additive, and the lead sulfide in the leach residues can be converted to lead carbonate by reacting with sodium carbonate solution using air as the oxidizing agent, and then the lead can be recycled in the whole process by dissolving the lead carbonate in NaOH solution. Over 90% of zinc can be extracted from the zinc sulfide, and over 95% of lead sulfide in leach residues can be converted. The Pb in leaded glass can be extracted in NaOH solution after mechanochemical reduction with metallic iron as additive. Over 90% of Pb can be extracted from the mechanochemical-reduced leaded glass, compared with less than 5% of Pb extraction for alkaline leaching of nonactivated samples, and 67% Zn extraction for alkaline leaching of activated samples for 2 h by planetary ball mill. Alkaline leaching process of smoke dust and lead oxide ore is conducted, which found that the leaching rate was over 90% after 30 min or longer. The resultant leaching residue contains lower than 1–2% of zinc, 0.5% of lead, 0.3% of copper, and 0.1% of cadmium, and over 35% of Fe, and may be classified as nonhazardous waste according to the results of leaching tests on the residues.

The thermodynamics of alkaline leaching of solid wastes bearing zinc or lead is carried out for the hydrometallurgy of zinc or lead hazardous wastes. The E-pH equilibrium diagrams of leaching systems of zinc or lead in different forms are drawn. In strong alkaline solution, most of zinc ions exist in the form of \( \mathrm{Zn}{\left(\mathrm{OH}\right)}_4^{2-} \). ZnO, ZnCO3, and Zn2SiO4 are the predominant mineralogical phases in solid wastes bearing zinc. ZnO and ZnCO3 can be dissolved directly by strong alkaline solution, while higher concentration of OH− is required to dissolve Zn2SiO4. PbO, PbS, PbCO3, and PbSO4 are the predominant mineralogical phases in solid wastes bearing lead. PbO, PbSO4, and PbCO3 can be dissolved in concentrated NaOH solutions, while the dissolution of PbS may be negligible. The equilibrium concentrations of Cd in leach solutions at 180 ~ 240 g/L NaOH is about 0.45 ~ 0.79 g/L. The dissolution of other impurities such as Fe, Cu, Co, Ni, Mg, Ca, etc. can be negligible.

In polarization-encoded free-space quantum communications, a transmitter on a satellite and a receiver in a ground station each have a respective polarization zero direction, by which they encode and decode every polarization quantum bit required for a quantum communication protocol. In order to complete the protocol, the ground-based receiver needs to track and compensate for the polarization zero direction of the satellite-based transmitter. Expressions satisfied by amplitudes of the s-polarization component and the p-polarization component are derived based on a two-mirror model, and a condition satisfied by the reflection coefficients of the two mirrors is given. A polarization tracking principle is analyzed for satellite-to-ground quantum communications, and quantum key encoding and decoding principles based on polarization tracking are given. A half-wave-plate-based dynamic polarization-basis compensation scheme is proposed in this paper, and this scheme is proved to be suitable for satellite-to-ground and intersatellite quantum communications.

In this study, a technology process including wet grinding, sieving and vacuum separation was proposed to recycle materials from waste liquid crystal display panel (LCDP). A wet crusher was used to break the glass and polarizing film of LCDP into granule first. Most liquid crystal molecules (94.10 wt. %) would be cleaned from LCDP under the impact of crusher and stayed in water. When the particle size of solid granule is less than 0.18 mm, the composition is pure glass, which accounted for 69.97 wt. % of the total granule. Pure polarizing film presents at more than 0.80 mm of particle size, which accounted for 11.47 wt. % of the total granule. The granule between 0.18∼0.80 mm, which contains glass and polarizing film bonded together, would be sent back to crusher to dissociate again. The glass part of LCDP contains indium of 219 ppm. Vacuum carbothermal reduction was employed to recycle indium from the glass part of LCDP. Based on the orthogonal optimization experiment, the optimal parameters were 950 °C, 30 min, 30 wt. % carbon adding amount and 1 Pa. Indium can be separated from the indium tin oxide (ITO) of glass part selectively. The recovery ratio of indium was 93 wt. %. During the physical process, all the valuable materials including indium, glass and organic materials can be recycled efficiently and eco-friendly, and there are no hazardous materials produced.

Ocean acidification is one of obvious and serious environmental issues caused by increasing CO2 levels in the atmosphere.Seawater pH has decreased by about 0.1 units since the industrial revolution and the carbonate equilibrium has been changing to become detrimental to the health of coral reef ecosystems around the world. Recent studies revealed that ocean acidification has decreased the calcification rate of scleractinian corals and other reef-building organisms,while promoting the dissolution rate.Models based on the Intergovernmental Panel on Climate Change(IPCC) business-as-usual emission scenarios suggest that atmospheric CO2 levels could approach 800 μL/L near the end of this century.Under this scenario,carbonate ion concentrations and aragonite saturation in surface seawater will be substantially reduced,and coral reef ecosystems around the world would experience net dissolution.No obvious influences were detected on the photosynthesis of coral symbionts,but the symbiosis system of corals and zooxanthellae could be affected.Corals would be more susceptible to bleaching with further ocean acidification,especially with simultaneously increasing temperatures.Studies showed that ocean acidification led to serious problems with larval recruitment,and affected the metabolism and reproduction of coral-reef organisms.It is believed that early developmental and reproductive stages of calcifying organisms are the points within a life cycle most vulnerable to environmental change.Laboratory experiments revealed that ocean acidification has negative impacts on the fertilization,cleavage,larva,settlement and reproductive stages of several marine calcifiers.Therefore future ocean acidification will potentially impact the population size and dynamics,as well as the community structure of calcifiers,and will have negative impacts on coral reef ecosystems. However,ocean acidification often has non-lethal and species-specific impacts on various species of coral.It is necessary to distinguish different species and different processes of metabolism in corals,when considering the impacts of ocean acidification.The research on ocean acidification is relatively new and the mechanisms behind ocean acidification affecting reef ecosystems are poorly understood.Nevertheless,the impacts of ocean acidification on coral reef ecosystems are indisputable.With increasing pressures from global climate change and human activities,other stress factors,such as global warming,sedimentation and eutrophication emerged,and would have synergistic impacts with ocean acidification on coral reef ecosystems,driving reefs toward the tipping point for functional collapse.Scientific evidence indicates that coral reefs have deteriorated rapidly in the past few decades and the future prospects for coral reefs are poor. Despite an urgent need for action,our knowledge on the impacts of ocean acidification on coral reef ecosystems and dependent organisms is still very limited.In order to clearly understand the effects of ocean acidification on coral disease(such as coral bleaching),we suggest that a long-term and systematic monitoring system,including laboratory and in-situ experiments,should be established.Physiological,molecular and ecological methods should be utilized to study the coral reef ecosystem on individual,population,community and ecosystem levels.Studies should also focus on the adaptive capability of marine organisms,which will be important to forecast how coral reef ecosystems will respond to ocean acidification.

OBJECTIVES: Previous studies have demonstrated that both low and high hemoglobin concentrations are predictive of adverse cardiovascular outcomes in various populations. However, an association of hemoglobin with the ankle-brachial index, which is widely used as a screening test for peripheral arterial disease, has not yet been identified. METHODS: We examined 786 subjects (236 women and 550 men) who received routine physical check-ups. The ankle-brachial index and several hematological parameters, including the hemoglobin level, hematocrit and red blood cell count and other demographic and biochemical characteristics were collected. Univariate and multivariate linear regression analyses were performed to assess the relationships between the ankle-brachial index and the independent determinants. Receiver operating characteristic curve analysis was conducted to calculate the cut-off level of hemoglobin for detecting a relatively low ankle-brachial index (less than 20% of all subjects, which was 1.02). RESULTS: The hemoglobin level, hematocrit and red blood cell count were correlated with the ankle-brachial index in the males (r=-0.274, r=-0.224 and r=-0.273, respectively, p

This study investigates the effect of using mechanical activation on the extraction of zinc from sphalerite in an alkaline solution containing lead carbonate. The combined mechanical activation and chemical leaching in a single operation (mechanochemical leaching) is found to be more effective in comparison with the separate mechanical activation and subsequent chemical leaching. A novel hydrometallurgical process for recovering Zn from sphalerite in alkaline solution via chemical conversion with PbCO 3 was developed in this work. In the stirred ball mill, the S originally present in sphalerite can be converted into PbS, while the Zn can be converted into Na 2 Zn(OH) 4 in the alkaline solution in presence of PbCO 3 . And then, the Pb in PbS deposited in the leach residues can be converted into PbCO 3 again in the Na 2 CO 3 solution. It was found that over 86% of Zn can be extracted from sphalerite when the leaching process is operated in 6 mol/L NaOH solution at 90 °C with PbCO 3 as additive, and stainless steel ball of 5 mm diameter as activation medium, the mass ratio of ball to raw materials of 30:1, Pb/ZnS of 0.9:1.

In the history of condensed matter physics, reinvestigation of a well-studied material with enhanced quality sometimes led to important scientific discoveries. A well-known example is the discovery of fractional quantum Hall effect in high quality GaAs/AlGaAs heterojunctions. Here we report the first single crystal growth and magnetoresistance (MR) measurements of the silver chalcogenide $\beta $-Ag$_2$Se (Naumannite), a compound has been known for the unusual, linear-field-dependent MR in its polycrystalline form for over a decade. With the quantum limit (QL) as low as 3 Tesla, a moderate field produced by a superconductor magnet available in many laboratories can easily drive the electrons in Ag$_2$Se to an unprecedented state. We observed significant negative longitudinal MR beyond the QL, which was understood as a `charge-pumping' effect between the novel fermions with opposite chiralities. Characterization of the single-crystalline Ag$_2$Se and the fabrication of electric devices working above the QL, will represent a new direction for the study of these exotic electrons., Comment: 17 pages, 5 figures

Compared with the semiconductors such as silicon and gallium arsenide which have been used widely for decades, semimetals have not received much attention in the field of condensed matter physics until very recently. The realization of electronic topological properties has motivated interest of investigations on Dirac semimetals and Weyl semimetals, which are predicted to show unprecedented features beyond the classical electronic theories of metals. In this letter for the first time we report the electric transport properties of a robust Weyl semimetal candidate proposed by recent theoretical calculations, TaAs. Our study shows that this bulk material manifests ultrahigh carrier mobility ($\mathrm{5\times10^5 cm^2/V\cdot{s}}$) accompanied by an extremely large, unsaturated linear magnetoresistance ($\mathrm{MR}$), which reaches 5400 at 10 Kelvins in a magnetic field of 9 Teslas and 2.47$\times$10$^4$ at 1.5 Kelvins in a magnetic field of 56 Teslas. We also observed strong Shubnikov-de Haas (SdH) oscillations associated with an extremely low quantum limit ($\sim$8 Teslas). Further studies on TaAs, especially in the ultraquantum limit regime, will help to extend the realization of the topological properties of these exotic electrons., 14 pages, 4 figures

Entrepreneurship is regarded as a process of opportunity, discovery, and alertness. In dynamic contexts, the enterprise or enterprising individuals need to make a proactive action on promising entrepreneurial opportunities. Shane and Venkataraman (2000) state that entrepreneurship “involves the processes of discovery evaluation, and exploitation of profitable opportunities,” thus, entrepreneur-ship can be considered a series of activities that include identifying opportunity; assessing and exploring; and delivering new products, services, governance structure, marketing methods, procedures, and materials to clients or markets that have not existed before.

We report the discovery of Weyl semimetal NbAs featuring topological Fermi arc surface states., Comment: Accepted by NaturePhysics (in press), Theoretical discovery of NbAs as a Weyl Fermion material (November 2014): http://www.nature.com/ncomms/2015/150612/ncomms8373/full/ncomms8373.html

We report the experimental discovery of Adler-Bell-Jackiw chiral anomaly in a Weyl semimetal crystal., Comment: 18 pages, 4 Figures; Related experimental papers at http://physics.princeton.edu/zahidhasangroup/index.html

DBSCAN is a very classic algorithm for data clus- tering, which is widely used in many fields. However, with the data scale growing much more bigger than before, the traditional serial algorithm can not meet the performance requirement. Recently, parallel computing based on CUDA has developed very fast and has great advantage on big data. This paper summarizes the algorithms proposed before and improves the performance of the old DBSCAN algorithm by using CUDA and parallel computing. The algorithm uses shared memory as much as possible compared with other algorithms and it has very good scalability. A data set is tested on the new version of DBSCAN. Finally, we analyze the results and give a conclusion that our algorithm is approximately 97 times faster than the serial version., Comment: 5 pages

Spectral clustering and cloud computing is emerging branch of computer science or related discipline. It overcome the shortcomings of some traditional clustering algorithm and guarantee the convergence to the optimal solution, thus have to the widespread attention. This article first introduced the parallel spectral clustering algorithm research background and significance, and then to Hadoop the cloud computing Framework has carried on the detailed introduction, then has carried on the related to spectral clustering is introduced, then introduces the spectral clustering arithmetic Method of parallel and relevant steps, finally made the related experiments, and the experiment are summarized.