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The supergiant Shizhuyuan W-Sn-Bi-Mo deposit is hosted by the Qianlishan granite, a small, highly fractionated granitic pluton (∼ 10 km 2 ) with multiple phases of intrusions within the Early Yanshanian granitoid province of SE China. Strong alteration of skarn and greisen that formed in the contact zone between the first and second phases of granite intrusions and Devonian limestone is responsible for the polymetallic mineralizations. SHRIMP U-Pb zircon analysis indicates that the two early phases of the Qianlishan granite formed contemporaneously at 152 ± 2 Ma. Metasomatic minerals (garnet, fluorite and wolframite) separated from the skarn and greisen yield a Sm-Nd isochron age of 149 ± 2 Ma that is interpreted as the formation age of the Shizhuyuan deposit. Therefore, the mineralization of the supergiant Shizhuyuan polymetallic deposit formed contemporaneously with, or very shortly after, the intrusion of the small, highly fractionated Qianlishan granite.

It has been widely reported that “naked” gold nanoparticles (Au NPs) without protectors have glucose oxidase (GOx)‐like activity, and the use of protectors can inhibit the GOx‐like activity. Here, “non‐naked” Au NPs with GOx‐like activity are synthesized by using protein as protector. Although “naked” Au NPs have peroxidase‐like activity and GOx‐like activity, the optimal pH ranges of the both activities are obviously different. Fortunately, as‐synthesized “non‐naked” Au NPs show the dual enzyme‐like activities at the same pH. So, “non‐naked” Au NPs can be described as “tandem nanozyme.” As another bonus, the participation of protein protector can stabilize the GOx‐like activity and make Au NPs modifiable. Even though Au NPs are connected with graphene oxide (GO), the GOx‐like activity is still not changed. Further, Au NPs‐GO nanocomposites are applied on the one‐pot nonenzymatic glucose colorimetric detection. The “non‐naked” gold not only broadens the species of tandem nanozymes, but also facilitates the functionalization of nanozymes, which is promising for immunoassay, biosensor, and medical treatment.

[1] The chemical index of alteration (CIA) and elemental ratios that are sensitive to chemical weathering, such as Ca/Ti, Na/Ti, Al/Ti, Al/Na, Al/K, and La/Sm, were analyzed for detrital sediments at Ocean Drilling Program Site 1148 from the northern South China Sea to reveal information of chemical weathering in the source regions during the early Miocene. High CIAvalues of $80, coupled with high Al/Ti and Al/Na and low Na/Ti and Ca/Ti, are observed for the sediments at $23 Ma, indicating a high chemical weathering intensity in the north source region, i.e., south China. This was followed by gradual decreases in Al/Ti, Al/Na, La/Sm, and Al/K ratios, as well as the CIAvalues, and increases in Ca/Ti and Na/Ti ratios. These records together with other paleoclimate proxies, such as black carbon d 13 C and benthic foraminifer d 18 O, give reliable information on the climate changes in south China. Our results show that the climate in south China was warm and humid in the early Miocene ($23 Ma) according to the chemical weathering records. The humidity in south China decreased from the early Miocene to Present with several fluctuations centering at approximately 15.7 Ma, 8.4 Ma, and 2.5 Ma, coincident with the global cooling since the middle Miocene. These climate changes implied that the summer east Asian monsoon has dramatically affected south China in the early Miocene, whereas the influence of the summer monsoon on this region has decreased continuously since that time, probably because of the intensification of the winter monsoon. Such an evolution for the east Asian monsoon is different from that for the Indian monsoon.

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A novel preconcentration method is presented for the determination of Mo isotope ratios by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) in geological samples. The method is based on the separation of Mo by extraction chromatography using N-benzoyl-N-phenylhydroxylamine (BPHA) supported on a microporous acrylic ester polymeric resin (Amberlite CG-71). By optimising the procedure, Mo could be simply and effectively separated from virtually all matrix elements with a single pass through a small volume of BPHA resin (0.5 ml). This technique for separation and enrichment of Mo is characterised by high selectivity, column efficiency and recovery (~100%), and low total procedural blank (~0.18 ng). A 100 Mo-97 Mo double spike was mixed with samples before digestion and column separation, which enabled natural mass-dependent isotopic fractionation to be determined with a measurement reproducibility of < 0.09‰ (d 98/95 Mo, 2s) by MC-ICP-MS. The mean d 98/95 Mo SRM 3134 (NIST SRM 3134 Mo reference material; Lot No. 891307) composition of the IAPSO seawater reference material measured in this study was 2.00 ± 0.03‰ (2s, n = 3), which is consistent with previously published values. The described procedure facilitated efficient and rapid Mo isotopic determination in various types of geological samples. Une nouvelle m ethode de pr e-concentration est pr esent ee pour la d etermination des rapports isotopiques du Mo par spectrom etrie de masse a source plasma et multi-collection (MC -ICP-MS) dans des echantillons g eologiques. La m ethode est bas ee sur la s eparation du Mo par Chromatographie d'extraction en utilisant du Nbenzoyle-N-ph enylhydroxylamine (BPHA) support e par une r esine polym ere d'ester acrylique microporeuse (Amberlite CG-71). En optimisant la proc edure, le Mo peutêtre simplement et efficacement s epar e de la quasitotalit e des el ements de la matrice avec un seul passage a travers un petit volume de r esine BPHA (0,5 ml). Cette technique de s eparation et d'enrichissement du Mo est caract eris ee par une grande s electivit e, une grande efficacit e et une grande r ecup eration de la colonne (~100%), et un faible total de la proc edure de blanc (~0,18 ng). Un double spike Mo 100 -Mo 97 a et e m elang e avec les echantillons avant la digestion et la s eparation sur colonne, ce qui a permis la d etermination du fractionnement isotopique naturel d ependant de la masse avec une reproductibilit e de mesure de < 0,09 ‰ ( d98/95 Mo, 2s) par MC -ICP-MS. La composition moyenne d 98/95 Mo SRM3134 (mat eriau de r ef erence NIST SRM 3134 Mo; Lot n°891307) de l'eau de mer de r ef erence IAPSO mesur ee dans cette etude est de 2,00 ± 0,03 ‰ (2s, n = 3), ce qui est coh erent avec les valeurs pr ec edemment publi ees. La proc edure d ecrite facilite une d etermination efficace et rapide des rapports isotopiques du Mo dans divers types d' echantillons g eologiques.Mots-clés : isotopes du molybd ene, N-benzoyle-Nph enylhydroxylamine, chromatographie d'extraction, pr econcentration, double spike, MC-...

Given the promising prospect of peroxidase-like nanozymes in colorimetric assay, it is interesting and significant to eliminate their oxidase-like activities and color interference for nanozyme-based colorimetric assay. Here, the enzyme-mimicking activity of GeO 2 nanomaterials is discovered. GeO 2 nanozymes exclusively possess peroxidase-like activity without oxidase-like characteristics, freeing the corresponding assay system from O 2 interference. Moreover, GeO 2 nanozymes are white, thereby eliminating the color interference of the nanozymes themselves in nanozymes-based colorimetric assay. Interestingly, compared with other metal oxides, GeO 2 nanozymes are easily decomposed by thiocholine, acetylcholinesterase (AChE)catalyzed hydrolysate, which triggers an ultrasensitive and anti-interference organophosphate pesticides assay process based on the irreversible inhibition of AChE. The proposed strategy about finding nanozymes with single activity without interference color will open avenues for improving the performance of colorimetric analysis systems based on nanozymes.