Mesozoic mineral deposits in South China include world-class deposits of W, Sn and Sb and those that provide the major sources of Ta, Cu, Hg, As, Tl, Pb, Zn, Au and Ag for the entire country. These ...deposits can be classified into polymetallic hydrothermal systems closely related to felsic intrusive rocks (Sn–W –Mo granites, Cu porphyries, polymetallic and Fe skarns, and polymetallic vein deposits) and low-temperature hydrothermal systems with no direct connection to igneous activities (MVT deposits, epithermal Au and Sb deposits). Recent studies have shown that they formed in the Triassic (Indosinian), Jurassic–Cretaceous (Early Yanshanian), and Cretaceous (Late Yanshanian) stages. Indosinian deposits include major MVT (Pb–Zn–Ag) deposits and granite-related W–Sn deposits. Early Yanshanian deposits are low-temperature Sb–Au and high-temperature W–Sn and Cu porphyry types. Many Late Yanshanian deposits are low-temperature Au–As–Sb–Hg and U deposits, and also include high-temperature W–Sn polymetallic deposits. The formation of these deposits is linked with a specific tectonothermal evolution and igneous activities. This special issue brings together some of the latest information in eight papers that deal with the origins and tectonic environments of mineral deposits formed in these stages. We anticipate that this issue will stimulate more interests in these ore deposits in South China.
At present, one of the major factors limiting the further improvement of inverted (p‐i‐n) perovskite solar cells (PSCs) is trap‐assisted non‐radiative recombination at the perovskite/electron ...transporting layer (ETL) interface. Surface passivation with organic ammonium salt is a powerful strategy to improve the performance of PSCs. Herein, an effective method by using propylamine hydroiodide (PAI) and 1,3‐diaminopropane dihydroiodide (PDADI) is reported to modify the perovskite/ETL interface. These two ammonium salts do not form new perovskite but directly passivate the defects on the perovskite surface after annealing. The results show that the PDADI‐modified perovskite films possess a lower surface defect density and less non‐radiative recombination as well as improved charge carrier transport. Based on this strategy, the PDADI‐modified p‐i‐n PSCs deliver an impressive efficiency of 25.09% (certified 24.58%) with an open‐circuit voltage of 1.184 V. Furthermore, the unencapsulated PDADI‐modified PSCs also exhibit good storage stability, retaining 91% of initial PCE at 65 °C in a N2 glove box for 1300 h. This strategy provides an efficient route to fabricate highly efficient and stable inverted p‐i‐n structured PSCs.
1,3‐diaminopropane dihydroiodide (PDADI) is introduced to modify the perovskite/electron transporting layer (ETL) interface. Based on this strategy, the PDADI‐modified p‐i‐n perovskite solar cells deliver an impressive efficiency of 25.09% (certified 24.58%) at the laboratory scale (0.071 cm2) with an open‐circuit voltage of 1.184 V.
Negative workplace behavior has received substantial research attention over the past several decades. Although we have learned a lot about the consequences of negative behavior for its victims and ...third-party observers, a less understood but equally important research question pertains to the consequences for bad actors: How does engaging in negative behavior impact one’s thoughts, feelings, and subsequent behaviors? Moreover, do organizational members experience costs or benefits from engaging in negative acts? We address these questions with an integrative review of empirical findings on various actor-centric consequences of a wide range of negative behaviors. We organize these findings into five dominant theoretical perspectives: affective, psychological-needs, relational, psychological-resources, and cognitive-dissonance perspectives. For each perspective, we provide an overview of the theoretical arguments, summarize findings of relevant studies underlying it, and discuss observed patterns and contradictory findings. By doing so, we provide a very tentative answer to our initial questions, contending that engaging in negative acts is a two-edged sword for actors and its costs seem to slightly prevail over its benefits. Nevertheless, we make this preliminary conclusion based upon an incomplete knowledge base. In order to further our understanding of actor-centric outcomes of negative behavior, we also identify several important research gaps and needed future research directions.
The abundances of trace elements including Sr, Ga and rare earth elements (REE) and halogens in apatite crystals from four intermediate-felsic plutons in the Zhongdian terrane in the Sanjiang region ...have been determined using electron microprobe and laser ablation inductively coupled plasma mass spectrometry to evaluate the potential of apatite as a petrogenic-metallogenic indicator. The selected plutons include one that is not mineralized (the Triassic Xiuwacu pluton, or the TXWC pluton), one that hosts a porphyry-type Cu deposit (the Pulang pluton, or the PL pluton), one that hosts a porphyry-type Mo deposit (the Tongchanggou pluton, or the TCG pluton), and one that hosts a vein-type Mo deposit (the Cretaceous Xiuwacu pluton, or the CXWC pluton). Except for the CXWC pluton, the other three plutons have adakite-like trace element signatures in whole rocks. The results from this study show that REE, Sr and halogens in apatite can be used to track magma compositions, oxidation states and crystallization history. Apatite crystals from the adakite-like plutons are characterized by much higher Sr/Y and δEu than the non-adakite-type pluton. This means that apatite, which is not susceptible to alteration, is a useful tool for identifying the adakite-like plutons that no longer preserve the initial Sr/Y ratios in whole rocks due to weathering and hydrothermal alteration. Based on apatite Ga contents and δEu values, it is inferred that the parental magmas for the two adakite-like plutons containing porphyry-type Cu and Mo mineralization are more oxidized than that for the non-adakite-type pluton containing vein-type Mo mineralization. Apatite crystals from the vein-type Mo deposit have much lower Cl/F ratios than those from the porphyry-type Cu and Mo deposits. Apatite crystals from the adakite-like pluton without Cu or Mo mineralization is characterized by much lower Cl/F ratios than those from the adakite-like plutons that host the porphyry-type Cu and Mo deposits. The results from this study confirm the apatite is a useful petrogenetic indicator as well as mineral exploration tool.
•Sr, REE and halogens in apatite can track magmas compositions and crystallization history.•The positive correlation of Ga contents with Eu negative anomalies in apatite can indicate oxidation states of magmas.•The combination of Sr/Y ratios and δEu in apatite can identify adakite-like plutons.•Apatite compositions can reveal different magmatic conditions associated with porphyry-type Cu and Mo mineralization, vein-type Mo mineralization and barren mineralization.
This paper provides the first evidence of the debt and stock market reaction to corporate green bond issuance in the simultaneously largest developing economy and largest emerging debt market, China. ...Utilizing a most comprehensive sample of Chinese green bonds, we document a pricing premium of corporate green bonds relative to conventional bonds. The economic magnitude of the Chinese green bond pricing premium is greatly larger than that of an international green bond documented in prior studies. The pricing premium of corporate green bonds is most pronounced for new issues from high corporate social responsibility (CSR) issuers and underwriters. It is also stronger for corporate issuers with less ownership concentration and held by long-term institutional investors. Further analysis reveals positive announcement stock returns for green bond new issues, consistent with the stakeholder value maximization theory that corporate engagement in sustainable financing practice increases firm value in a long run and thus is favored by shareholders.
•This paper provides the first evidence of the debt and stock market reaction to green bond issuance in China, the largest home country for green bonds as of 2018.•We document a robust pricing premium of corporate green bonds relative to otherwise•This study is novel in uncovering the important roles of issuers, underwriters and bond investors in determining the green bond price premium.•Stock market investors positively react to the announcements of green bond new issues.
Counterfeiting is a global epidemic that is compelling the development of new anticounterfeiting strategy. Herein, we report a novel multiple anticounterfeiting encoding strategy of invisible ...fluorescent quick response (QR) codes with emission color as information storage unit. The strategy requires red, green, and blue (RGB) light-emitting materials for different emission colors as encrypting information, single excitation for all of the emission for practicability, and ultraviolet (UV) excitation for invisibility under daylight. Therefore, RGB light-emitting nanoscale metal–organic frameworks (NMOFs) are designed as inks to construct the colorful light-emitting boxes for information encrypting, while three black vertex boxes were used for positioning. Full-color emissions are obtained by mixing the trichromatic NMOFs inks through inkjet printer. The encrypting information capacity is easily adjusted by the number of light-emitting boxes with the infinite emission colors. The information is decoded with specific excitation light at 275 nm, making the QR codes invisible under daylight. The composition of inks, invisibility, inkjet printing, and the abundant encrypting information all contribute to multiple anticounterfeiting. The proposed QR codes pattern holds great potential for advanced anticounterfeiting.
The bin packing problem has a wide range of applications in industry. With the upgrade of the task difficulty, the traditional 2d rectangular layout algorithm can no longer meet the needs of modern ...industry, such as express packing task and exoplanet ore collection task. The express or ore samples come in heterogeneous shapes so they cannot all be treated as rectangular pieces. In this paper, we propose a three-stage method called covering, corner-searching and occupying (C,S&O) to solve the two-dimensional multishape part packing problem. The objective of the packing problem variant is to ensure maximum use of the raw material and minimize the trim loss. The algorithm cannot make use of information about the sequence of future objects that are going to arrive, only knowing the shape and size of the coming one, and the coming part must be packed into the bin immediately after its arrival without buffering or readjusting. The method of C,S&O hybridizes the idea of "gold corners, silver edges and grass belly" in the Chinese game Go and the method of finding picture corners in machine vision. In the first stage, the rectangular bin and the coming part are transformed into matrix representation, and generating the position matrix that indicates possible ways of packing the part into the bin. In the second stage, the suitable layout position of the coming part is obtained using machine vision image processing technology for reference. The third stage is calculating the environment matching degree to determine the current optimal placement orientation. In order to facilitate the display of the simulation results, only three shapes of parts are considered in the simulation, rectangle, circle and triangle. The experimental results show the effectiveness of this method. Consulting the literature, it is found that this paper is the first to propose a layout method for multishape manufacturing parts.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Multitarget assay with single detection modality from individual stimulation mode has aroused great attention. Here, we realize multitarget detection with the color change as signal source from ...single white light-emitting metal–organic frameworks (MOFs) under single wavelength excitation for the first time. The white light-emitting MOFs are prepared by carefully tuning the ratio of Eu3+, Tb3+, and Dy3+ ions to obtain trimetal MOFs; 5-boronoisophthalic acid (5-bop) provides additional selectivity as ligand. Based on antenna effect, 5-bop is excited to produce its triplet-state, which sensitizes the Ln3+ ions for the white emission. Thus, all of the fluorescence emission is achieved under single wavelength excitation at 275 nm, while any factors affecting the procedure result in the modulation of emission for diverse wavelengths. The trimetal MOFs display distinctive emission colors after interacting with different targets, including metal ions, anions, small molecule, and even biomolecule as a Lab-on-MOFs system. This system shows higher integration degree and simpler preparation and sensing procedures than other multitarget detection strategies.
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