Search

The effects of cations stress of magnesium ion and sodium ion on the low-grade nickel sulfide ore oxidative leaching in simulated sulfuric acid solutions were investigated. This study was performed in two courses, including the effect of the cations on the valuable metals leaching efficiencies of the nickel ore and its influences on the electrochemical oxidation behavior of the nickel ore. The leaching results present that parts of magnesium-containing gangues and ferrous sulfide are preferentially dissolved into lixivium, and the leaching efficiencies of Ni and Cu decreased much related to the leached concentrations of Mg2+ increased. The results of electrochemical measurements show that the oxidation leaching of the low-grade nickel sulfide ore is controlled by the intermediates oxidative diffusion. Mg2+, as well as Na+, affects the transformations of the Fe3+/Fe2+ couple and sulfur-containing species, and those cations are apt to be attracted by the anions and directionally adhere to the negative active site of the metal sulfide surface, causing an increase in the electrochemical activities, which facilitates the electron transfer between the ore and leaching mediums. By comparative study of the role of Mg2+ and Na+, it is found that Mg2+ negatively affects the oxidative diffusion of the intermediates through promoting the generation of a compact film, which lowers the metals leached efficiencies, and the unfavorable effect of Na+ tends to be the coupled effect of the leached Mg2+ and Fe3+.

Additional file 1.

Additional file 1: Figure S1. Full-length blot of Bax protein expression level. Figure. S2. Full-length blot of Deptor protein expression level. Figure. S3. Full length blot of ��-tubulin protein expression level. Figure S4. Full-length blot of Stat1 protein expression level. Figure S5. Full-length blot ��-actin protein expression level. Figure S6. Full-length blot of Rps6ka1 protein expression level. Figure S7. Full length blot GAPDH protein expression level.

In this paper, a new method for the comprehensive recovery and recycle of jarosite residues (JR) is proposed. By direct reduction followed by magnetic separation, lead, zinc and iron are separated and recovered from JR and sulfur is fixed. The non-magnetic tails (NMT) of the magnetic separation is used for removing of Cd, As and Pb heavy metal ions from acidic wastewater of zinc hydrometallurgy. Test work results showed that the volatilization rates of lead and zinc were 96.97% and 99.89%, respectively, the sulfur fixation rate with CaO was 98.91% under optimal conditions of reduced roasting at 1523 K for 60 min. A magnetic iron concentrate was obtained containing 95.68% iron at a recovery of 76.26% by grinding-magnetic separation process. The removal rates of Cd, As and Pb ions were 99.98%, 93.75% and 99.80% respectively. The content of Cd, As and Pb ions in the treated wastewater met the emission standards at 120 g/L NMT dosage and for a contact time of 90 mins. The proposed method is considered as an environmentally-friendly and efficient approach to the comprehensive recovery and recycle of JR and the removal of toxic cadmium, arsenic and lead ions from acidic wastewater of zinc hydrometallurgy.

Siamese neural network has been well investigated by tracking frameworks due to its fast speed and high accuracy. However, very few efforts were spent on background-extraction by those approaches. In this paper, a Pixel to Global Matching Network (PG-Net) is proposed to suppress t+he influence of background in search image while achieving state-of-the-art tracking performance. To achieve this purpose, each pixel on search feature is utilized to calculate the similarity with global template feature. This calculation method can appropriately reduce the matching area, thus introducing less background interference. In addition, we propose a new tracking framework to perform correlation-shared tracking and multiple losses for training, which not only reduce the computational burden but also improve the performance. We conduct comparison experiments on various public tracking datasets, which obtains state-of-the-art performance while running with fast speed.

Recently, the development of methods for the cleanup of large-scale oil spills or organic pollutants from water has been attracting global attention. However, traditional techniques suffer from the limits of low efficiency and high operation cost. Herein, we propose a high efficiency, large-scale and easy operation approach to fabricate a hydrophobic and oleophilic high density polyethylene microfiber bundles with interconnected microchannels for oil/water separation. The microfiber bundles with high porosity, excellent absorption capacity and large water contact angle are continuously fabricated by a melt extrusion and leaching technique. More importantly, they are readily cleaned by centrifugation and exhibit excellent shape-recoverable property, which are very promising for the cleanup of large-scale oil spills. This study provides a great promising way to fabricate multifunctional polymer materials by using common polymer molding method.

Vehicle taillight recognition has been well investigated recent years. However, few methods can be applied in practical because of the time consumption or less recognition accuracy. In this paper, we design a light-weight framework for vehicle taillight recognition in real-time, which is divided into detection and recognition stage. To achieve this purpose, Finer Detection Block and dense anchor regression are utilized to improve the robust of detection stage. In addition, a Siamese CNN-GRU network is proposed, which not only captures the short-time difference but also learns the long-time flash features. We conduct ablation experiments to verify our proposed method, which obtains a mean recall of 94.34% with 103 FPS on 1080Ti.

From the viewpoint of reduction of the global warming, the utilization and application of the renewable energies are required. Among various renewable energies, plant biomass is one of the most important energy resources. In the current process of bioconversion of plant biomass to value-added products, plant biomass is hydrolyzed by cellulolytic enzymes from fungi such as Trichoderma reesei and the resultant fermentable monosaccharides are fermented to biofuels etc. by yeasts or bacteria. On the other hand, “consolidated bioprocessing (CBP)” is widely recognized as the efficient strategy for simultaneous hydrolysis and fermentation of biomass using cellulolytic anaerobic bacteria. A novel hemicellulase Abf62A-Axe6A from Ruminiclostridium josui was biochemically characterized and its host-vector system was established for better use of this bacterium for CBP. R. josui Abf62A-Axe6A is a modular enzyme consisting of an N-terminal signal peptide, a catalytic module of glycoside hydrolase family 62 (GH62), a family 6 carbohydrate binding module (CBM6), a dockerin module and another catalytic module of carbohydrate esterase family 6 (CE6) in order from the N-terminus. Therefore, three recombinant enzymes, RjAbf62A-Axe6A consisting of 4 modules devoid of the signal peptide, RjAbf62A-CBM6 consisting of GH62 and CBM6 and RjAxe6 consisting of CE6 only, were produced by Escherichia coli recombinants and biochemically characterized. RjAbf62A-Axe6 was highly active toward arabinoxylan and moderately active toward sugar beet arabinan, releasing mainly arabinose. Analysis of the hydrolysis products of arabinoxylooligosaccharides indicated that RjAbf62A-Axe6 released not only α-1,2- and α-1,3-linked arabinofuranoses from singly substituted xylosyl residues but also from doubly substituted xylosyl residues. RjAbf62A-Axe6A efficiently hydrolyzed 32-α-L-arabinofuranosyl xylobiose (A3X) to release arabinose, and the activity toward A3X was stronger than toward 33-α-L-arabinofuranosyl xylotetraose (XA3XX), 23-α-L-arabinofuranosyl xylotriose (A2XX) and (23,33-di-α-L-arabinofuranosyl xylotriose) A2,3XX. RjAbf62A-Axe6A seemed to prefer Araf of substituted xylosyl residues located at non-reducing end and the 1,3-linked Araf residues in doubly substituted xylosyl residues. The enzyme showed a weak activity toward linear 1,5-α-L-arabinan and arabinooligosaccharides, indicating that it had an exo-α-1,5-L-arabinofuranosidase activity. Surprisingly, RjAbf62A-Axe6 demonstrated an endoxylanase activity toward birchwood and beechwood xylans and xylooligosaccharides. RjAbf62A-Axe6 is the first GH62 enzyme having arabinofuranosidase and endoxylanase activities. Both RjAbf62A-Axe6 and RjAxe6 had an acetylxylan esterase activity toward insoluble wheat arabinoxylan. R. josui host-vector system has not yet been established because of the existence of a restriction and modification system in R. josui. A restriction endonuclease RjoI was purified from R. josui cell extract using column chromatography and characterized. The results showed that RjoI is an isoschizomer of DpnI, recognizing the sequence 5’-GmetATC-3’, where the A nucleotide is Dam-methylated. RjoI cleaved the recognition sequence between the A and T nucleotides, producing blunt ends. Plasmids prepared from E. coli C2925 (dam−/dcm−) could be introduced into R. josui by electroporation. The highest transformation efficiency of 6.6 × 103 transformants/μg of DNA was obtained using a square wave pulse (750 V, 1 ms). When the R. josui cel48A gene, devoid of the dockerin encoding region, cloned into newly developed plasmid pKKM801 was introduced into R. josui, a truncated form of Cel48A, RjCel48AΔdoc, was detected in the culture supernatant but not in the intracellular fraction. This is the first report on the establishment of the fundamental technology for molecular breeding of R. josui., 本文 / Graduate School of Bioresources Mie University, 114p

Impaired motor function, due to the dysfunction of the basal ganglia, is the most common syndrome of hepatic encephalopathy (HE), and its etiology remains poorly understood. Neural oxidative stress is shown to be the major cellular defects contributing to HE pathogenesis. Mitochondrial uncoupling protein 2 (UCP2) has been implicated in neuroprotection in several neurological disorders. We explored the neuroprotective role of UCP2 within the substantia nigra pars reticulate (SNr), the output structure of the basal ganglia, in HE. The toxin thioacetamide (TAA) induced HE mice showed hypolocomotion, which was associated with decreased ATP levels and loss of antioxidant substances SOD and GSH within the SNr. Stable overexpression of UCP2 via AAV-UCP2 under the control of the UCP2 promoter in bilateral SNr preserved local ATP level, increased antioxidant substances, and ameliorated locomotion defects after severe liver failure. Contrary to UCP2 overexpression, targeted knockdown of UCP2 within bilateral SNr via AAV-UCP2 shRNA exacerbated the impaired mitochondrial dysfunction and hypokinesia in HE mice. The modulatory effects of UCP2 was due to mediation of K+-Cl- cotransporter-2 (KCC2) expression on GABAergic neurons of SNr. Taken together, our results demonstrate that UCP2 exerts a neural protective role at the subcortical level by increasing the resistance of neurons to oxidative stress, which may offer a novel therapeutic target for the treatment of motor dysfunction diseases.

The detection of partial discharge of power transformer is important for the safe operation of a power system. The direction of arrival is an important part of ultrasonic array detection. Classic DOA estimation algorithms based on subspace analysis do not perform well under the conditions of low SNR and small snapshot numbers. The problem with using an improved algorithm is that it requires a huge amount of calculation. In this paper sparse signal decomposition is applied to spatial spectrum estimation. The authors derived the model of array signal direction finding by the use of matching pursuit algorithm, setting up overcomplete dictionaries for different types of sensor array and simulating different types of sensor array receiving signals. Simulations and experiments show that direction finding based on MP decomposition method performs better than using the MUSIC algorithm under the conditions of low SNR and small snapshot numbers, and that the influence of array types is less.

Polyaniline-modified TiO2 nanotube arrays (PANI/TNTs) were fabricated by a constant voltage electropolymerization method. The self-organized TiO2 nanotube arrays with an inner diameter of approximately 100 nm and a length of 4 μm were prepared by a two-step anodization at 20 V for 3 h, and then the polyaniline was deposited on the surface of the TiO2 nanotube arrays. The phase composition, morphology and property of PANI/TNTs were characterized by X-ray diffraction, scanning electron microscopy, fourier transform infrared spectroscopy and UV-vis diffuse reflectance spectroscopy. The prepared PANI/TNTs showed enhanced visible light absorption and corresponding visible light photocatalytic activity. Furthermore, the PANI/TNTs also exhibited higher electrochemical behaviour than that of TiO2 nanotube arrays.

The vibration signal of a gear system is selected as the original information of fault diagnosis and the gear system vibration equipment is established. The vibration acceleration signals of the normal gear, gear with tooth root crack fault, gear with pitch crack fault, gear with tooth wear fault and gear with multi-fault (tooth root crack & tooth wear fault) is collected in four kinds of speed conditions such as 300 rpm, 900 rpm, 1200 rpm and 1500 rpm. Using the method of wavelet threshold de-noising to denoise the original signal and decomposing the denoising signal utilizing the wavelet packet transform, then 16 frequency bands of decomposed signal are got. After restructuring the decomposing signal and obtaining the signal energy in each frequency band, the signal energy of the 16 bands is as the shortlisted fault characteristic data. Based on this, using the methods of principal component analysis (short for PCA) and kernel principal component analysis (short for KPCA) to extract the feature from the fault features of shortlisted 16-dimensional data feature, then the effect of reducing dimension analysis are compared. The fault classifications are displayed through the information that got from the first and the second principal component and kernel principal component, and these demonstrate they have a different and good effect of classification. Meanwhile, the article discusses the effect of feature extraction and classification that caused by the kernel function and the different options of its parameters. These provide a new method for a gear system fault feature extraction and classification.

The solubilities of 1-fluoro-4-(methylsulfonyl)benzene in five pure organic solvents (ethanol, ethyl acetate, acetone, toluene, and chloroform) at temperatures ranging from (288.40 to 331.50) K under atmospheric pressure were measured experimentally by the dynamic method with a laser monitoring apparatus. It was found that the solubilities in different solvents decreased in the order chloroform > acetone > ethyl acetate > toluene > ethanol. The experimental data were well-correlated using the modified Apelblat equation, with average relative deviations of less than 2.92 % and root-mean-square deviations of no more than 0.30 %.

Gegenstand der Erfindung ist ein Verfahren zur Herstellung von Polyurethan-Hartschaumstoffen durch Umsetzung von a) Polyisocyanaten mit b) Verbindungen mit mindestens zwei mit Isocyanatgruppen reaktiven Wasserstoffatomen in Anwesenheit von c) Treibmitteln, dadurch gekennzeichnet, dass die Komponente b) mindestens einen Polyesteralkohol bi) mit einer Funktionalität von 1,5 bis 4,5 und einer Hydroxylzahl im Bereich zwischen 200 und 800 mgKOH/g enthält, zu dessen Herstellung mindestens eine aliphatische, mindestens zweifunktionelle Carbonsäure, mindestens ein aliphatischer, mindestens zweifunktioneller Alkohol sowie mindestens ein Pflanzenöl, und/oder mindestens eine Fettsäure eingesetzt wurde.