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The Tiegelongnan Cu (Au, Ag) deposit in central Tibet contains more than 10 Mt of copper ranking 29thin the world. It is characterized by typical porphyry-epithermal alteration and mineralization. In order to improve the understanding of porphyry-epithermal copper deposit in Tibet, new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism. Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous (about 120 Ma) granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean. Sulfur mainly comes from deep magma, and ore-forming fluid is affected by both magmatic and meteoric water. The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America. The cover of the Meiriqiecuo Formation volcanic rocks, Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit. The formation, preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet.

The Tiegelongnan Cu (Au, Ag) deposit in central Tibet contains more than 10 Mt of copper ranking 29thin the world. It is characterized by typical porphyry-epithermal alteration and mineralization. In order to improve the understanding of porphyry-epithermal copper deposit in Tibet, new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism. Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous (about 120 Ma) granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean. Sulfur mainly comes from deep magma, and ore-forming fluid is affected by both magmatic and meteoric water. The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America. The cover of the Meiriqiecuo Formation volcanic rocks, Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit. The formation, preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet.

Many large and super-large copper deposits have been discovered and explored in the Tibet Plateau, which makes it the most important copper resource reserve and development base in China. Based on the work of the research team, the paper summarizes the geological characteristics of the main copper deposits in Tibet and puts forward a further prospecting direction. A series of large accumulated metal deposits or ore districts from subduction of Tethys oceanic crust to India-Asia collisionhave been discovered, such as Duolong Cu (Au) ore district and Jiama copper polymetallic deposit. The ore deposits in the Duolong ore district are located in the lowstand domain, the top of lowstand domain, and the highstand domain of the same magmatic-hydrothermal metallogenic system, and their relative positions are the indicators for related deposits in the Bangong Co-Nujiang metallogenic belt. The polycentric metallogenic model of the Jiama copper polymetallic deposit is an important inspiration for the exploration of the porphyry mineralization related to collision orogeny. Further mineral exploration in the Tibet Plateau should be focused on the continental volcanic rocks related to porphyry-epithermal deposits, orogenic gold deposits, hydrothermal Pb-Zn deposits related to nappe structures, skarn Cu (Au) and polymetallic deposits, and the Miocene W-Sn polymetallic deposits.

BRI1-EMS-SUPPRESSOR 1 (BES1) transcription factor is closely associated with the brassinosteroid (BR) signaling pathway and plays an important role in plant growth and development. SLB3is a member of BES1 transcription factor family and its expression was previously shown to increase significantly in tomato seedlings under drought stress. In the present study, we used virus-induced gene silencing (VIGS) technology to downregulate SLB3expression to reveal the function of the SLB3gene under drought stress further. The downregulated expression of SLB3weakened the drought tolerance of the plants appeared earlier wilting and higher accumulation of H2O2and O2−·, decreased superoxide dismutase (SOD) activity, and increased proline (PRO) and malondialdehyde (MDA) contents and peroxidase (POD) activity. Quantitative real-time PCR (qRT-PCR) analysis of BR-related genes revealed that the expression of SlCPD, SlDWARFand BIN2-related genes was significantly upregulated in SLB3-silenced seedlings under drought stress, but that the expression of TCH4-related genes was downregulated. These results showed that silencing the SLB3gene reduced the drought resistance of tomato plants and had an impact on the BR signaling transduction which may be probably responsible for the variation in drought resistance of the tomato plants.

Zinc finger-homeodomain proteins (ZF-HDs) are transcription factors that regulate plant growth, development, and abiotic stress tolerance. The SL-ZH13gene was found to be significantly upregulated under drought stress treatment in tomato (Solanum lycopersicum) leaves in our previous study. In this study, to further understand the role that the SL-ZH13gene plays in the response of tomato plants to drought stress, the virus-induced gene silencing (VIGS) method was applied to downregulate SL-ZH13expression in tomato plants, and these plants were treated with drought stress to analyze the changes in drought tolerance. The SL-ZH13silencing efficiency was confirmed by quantitative real-time PCR (qRT-PCR) analysis. In SL-ZH13-silenced plants, the stems wilted faster, leaf shrinkage was more severe than in control plants under the same drought stress treatment conditions, and the mean stem bending angle of SL-ZH13-silenced plants was smaller than that of control plants. Physiological analyses showed that the activity of superoxide dismutase (SOD) and peroxidase (POD) and the content of proline (Pro) in SL-ZH13-silenced plants were lower than those in control plants after 1.5 and 3 h of drought stress treatment. The malondialdehyde (MDA) content in SL-ZH13-silenced plants was higher than that in control plants after 1.5 and 3 h of drought stress treatment, and H2O2and O2–· accumulated much more in the leaves of SL-ZH13-silenced plants than in the leaves of control plants. These results suggested that silencing the SL-ZH13gene affected the response of tomato plants to drought stress and decreased the drought tolerance of tomato plants.

Facile structural modification of α-MnO2viasingle incorporation of Ag element was applied to achieve high-efficiency oxidation removal of benzene, particularly under wet gas. Ag+ions could enter the MnO2structure by partially replacing the tunnel K+ions, leading to lower crystallinity, smaller crystallite and distorted lattice arrangement. Due to electron transfer from Ag+to lattice oxygen, Ag decoration weakened Mn-O bonds and the bulk lattice oxygen became more mobile to migrate towards the Ag-MnO2surface, resulting in the larger number of surface lattice oxygen. Along with the abundance of oxygen species, the reactivity of surface adsorbed oxygen and lattice oxygen was significantly improved as well by Ag modification. All these factors were favorable to the complete C6H6-to-CO2conversion. Gaseous benzene could be directly oxidized by oxygen species over the pristine MnO2catalyst, while the adsorptive activation of gaseous benzene was required for the Ag-MnO2before further oxidation. As to the Ag-MnO2’s endurability of moisture-aroused inactivation, Ag species oppressed water adsorption in the form of strong adsorbate, thus preventing structural damage of the catalyst during humid benzene oxidation. Moreover, water molecules could enhance the “Ag-MnO2vs. adsorbed benzene” interaction, which increased the oxidation efficiency of adsorbed benzene. However, the strong binding of water vapor with the MnO2surface would cause strong restriction of gaseous benzene from approaching the surface oxygen species, resulting in much less benzene being oxidized under wet gas.

Catalytic oxidation at ambient temperature dominates priority in airborne formaldehyde elimination. Herein, the effects of Li+, Na+and K+on the catalytic activity of Ag-CoOxcomposite were comparatively studied. Systematic methods were applied to investigate the factors influencing catalytic activity. Compared with the cases of Na+and K+, for which the combination with Ag species respectively deteriorated and limitedly increased formaldehyde removal, the incorporation of Li+greatly boosted formaldehyde degradation. Characterization results certify that the largest amount of chemically adsorbed active oxygen was crucial to the excellent performance of Li-Ag-CoOx, and the advanced oxidizing property can be rationalized by the strong interaction between the exclusively formed AgCoO2and the catalyst parent. This is the first time to clarify the roles of varied alkaline metals in the complete oxidation of formaldehyde catalyzed by Ag-CoOxmaterials. Effects of process variables were additionally investigated to uncover the catalyst suitability for in-field application.

Ochratoxin A (OTA) is a common foodmycotoxin that is widely distributed and highly toxic. The establishment of a sensitive, stable, and rapid OTA detection method is important to protect human health and food safety. In this study, a label-free aptamer fluorescent sensor was developed for the rapid determination of OTA by optimizing the concentration of fluorescent dyes, the addition of exonuclease I, and the reaction time. Under the optimal experimental conditions, the fluorescence intensity of SYBR Gold showed a linear relationship with the OTA concentration in the range of 5–500 ng/mL with a correlation coefficient of 0.9966 and a detection limit of 1.49 ng/mL, indicating good selectivity. The method was applied to determine OTA in red wine, with recovery rates ranging from 89.0% to 113.6% and relative standard deviations ranging from 4.3% to 6.2%. Compared with other aptamer-based OTA detection methods, the proposed method has higher sensitivity and selectivity and lower cost. Thus, the proposed method has good application prospects in OTA determination.

The article presents a decision-making analysis on the proper construction scale of Beijing Olympic Games. It presents the engineering items and procedures of the pre-construction stage, and the method to control the entire construction scale. It hypothesizes the eight factors to consider in planning and designing procedure. It founds out the feasibility and possibility of applying the AHP method to control the construction scale of the National Stadium.

C10H9Cl2NO4, orthorhombic, Pbca, a= 11.151(2) Å, b= 7.0923(14) Å, c= 29.243(6) Å, V= 2312.7(8) Å3, Z= 8, Rgt(F)= 0.0459, wRref(F2)= 0.1223, T= 293 K.