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In this study, the Pb/U fractionation between zircon and uraninite during femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry （fs-LA-ICP-MS） analysis was studied in detail. The results show significant Pb/U fractionation between zircon and uraninite during fs-LA-ICP-MS analysis that when calibrated against the zircon standard M257, the obtained U-Pb age of the Chinese national uraninite standard GBW04420 is 17% older than the recommended value. Thus, the accurate in-situ U-Pb dating of uraninite by LA-ICP-MS requires matrix-matched external standards for calibration. Uraninite in thin sections of two U-mineralized leucogranite from the Gaudeanmus in Namibia was analyzed by a fs-LA-ICP-MS equipped with a Signal Smooth Device （SSD）, using laser spot and frequency of 10 μm and 1 Hz, respectively. When calibrated using GBW04420 as the external standard, two samples give weighted mean 2066pb/238U ages of 504±3 Ma （2σ, n=21） and 503±3 Ma （2σ, n=22）, and only one of two samples yields a concordia U-Pb age of 507±1 Ma （2or, n=21）. These results are consistent with ID-TIMS U-Pb ages of 509±1 and 508±12 Ma and are also indistinguishable from zircon U-Pb upper intercept ages of 506±33 Ma （2σ, n=29） and 501±51 Ma （2σ, n=29）. The present study shows that in-situ U-Pb dating of uraninite can deliver more reliable formation ages of the deposit than dating coeval high-U zircon because the latter commonly suffer significant Pb loss after formation. Our results confirm that GBW04420 is an ideal matrix matching standard for in-situ U-Pb dating of uraninite.

An in-situ microanalysis of Pb isotopic compositions in sulfide minerals is carried out by using femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry （fsLA-MC-ICP-MS）. High-temperature-activated carbon was used to filter Hg contained in the carrier gas, which reduced the Hg background signal by 48% and also lowered the detection limit of the analysis. Fractionation and mass discrimination effects existing in the ICP-MS analytical processes were corrected using an internal reference T1 in conjunction with an external reference NIST SRM 610. The proposed method was used to an- alyze the Pb isotopic compositions of chalcopyrite, pyrite, and sphalerite from the Dulong Sn-Zn-In polymetallic ore district. The results showed that in this ore district, the sulfide minerals and different grains of the same sulfide mineral show a large variation in Pb content up to 1000-fold. The studied pyrites show relatively higher Pb contents and homogeneous Pb isotopic compositions, whereas the sphalerites have low Pb contents but most variable Pb isotopic compositions. It is suggested that the large variation of Pb isotopic composition may reflect a late hydrothermal superimposition on the primary sulfide formation. In addition, radiogenic Pb accumulated by radioactive decay of trace amounts of U over time in the host minerals may also be one of the causes for the large variation range of Pb content and Pb isotopic composition of those low-Pb sphalerites. Chalcopyrite and sphalerite grains with Pb content greater than 10 ppm presented a consistent Pb isotopic distribution, whereas all the sulfide grains with Pb content greater than 100 ppm had consistent Pb isotopic composition within 2s measurement uncertainties. The in-situ analysis of Pb isotopic composition agreed well with the results obtained by conventional chemical methods within 2s measurement uncertainties, indicating that the data obtained by fsLA-MC-ICP-MS are reliable. Additionally, this study indicates that the Pb isotopic composition could truthfully record the source of ore-forming minerals only for sulfide minerals with high Pb content. On the contrary, the Pb isotopic composition of low-Pb sulfide minerals may be affected by trace amounts of U in the host minerals that may lead to a highly radiogenic Pb isotope ratio. Alternatively, it is also possible that late fluid metasomatic overprinting may alter the Pb isotopic compositions.

Three-dimensional （3D） hierarchical Pt-Cu tetragonal, highly branched, and dendritic superstructures have been synthesized by a facile template-free hydrothermal approach, showing growth patterns along （111, 110）, （111）, and （100） planes, respectively. These structures have been characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD）, energy dispersive X-ray spectroscopy （EDX）, inductively coupled plasma optical emission spectrometry （ICP-OES） and a detailed formation mechanism has been developed, which shows that the in situ formed 12 and the galvanic replacement reaction between Cu and Pt4, may guide the formation of these superstructures. The comparative electrocatalytic properties have been investigated for methanol and ethanol oxidation. Due to their interconnected arms, sufficient absorption sites, and exposed surfaces, these superstructures exhibit enhanced electrocatalytic performance for electro-oxidation of methanol and ethanol when compared with commercial Pt/C and Pt black.

Crystalline and nanostructured cobalt （CoFe2O4）, nickel （NiFe2O4）, zinc （ZnFe2O4） and manganese （MnFe2O4） spinel ferrites are synthesized with high yields, crystallinity and purity through an easy, quick, reproducible and low-temperature hydrothermal assisted route starting from an aqueous suspension of copredpitated metal oxalates. The use of water as a reaction medium is a further advantage of the chosen protocol. Additionally, the zinc spinel is also prepared through an alternative route combining copredpitation of oxalates from an aqueous solution with thermal decomposition under reflux conditions. The nanocrystalline powders are obtained as a pure crystalline phase already at the extremely low tem- perature of 75 ℃ and no further thermal treatment is needed. The structure and microstructure of the prepared materials is investigated by means of X-ray powder diffraction （XRPD）, while X-ray photoelectron spectroscopy （XPS） and inductively coupled plasma-atomic emission spectroscopy （ICP-AES） analyses are used to gain information about the surface and bulk composition of the samples, respectively, confirming the expected stoichiometry. To investigate the effect of the synthesis protocol on the morphology of the obtained ferrites, transmission electron microscopy （TEM） observations are performed on selected samples. The magnetic properties of the cobalt and manganese spinels are also investigated using a superconducting quantum device magnetometer （SQUID） revealing hard and soft ferrimagnetic behavior, respectively.

South China is famous for the extensive magmatism and polymetallic mineralization that took place there in the Mesozoic. Shilu is a large porphyry–skarn Cu–Mo deposit in the Yangchun Basin, South China. The lithology of the Shilu intrusion is granodiorite and quartz diorite, both of which are high-K calc-alkaline series, with high Sr（[400 ppm） content along with low Y and Yb contents. Most of the samples have characteristics of adakite except for a few samples that have slightly higher Y and Yb contents, which may be plausibly explained by crustal contamination. Laser Ablation Inductively Coupled Plasma Mass Spectrometry zircon U–Pb dating revealed ages between 106.6 ± 1.3 and 103.9 ± 0.5 Ma, with multiple magmatic pulses. Molybdenite Re–Os isochron age of 102.2 ± 2.9 Ma（MSWD = 9.4） was determined, which is identical to the youngest zircon U–Pb age（103.9 ± 0.5 Ma） within error.The Shilu intrusion has high oxygen fugacity as indicated by high zircon Ce^4＋/Ce^3＋ and EuN/EuN^＊ ratios. Considering the geochemical characteristics（high Sr, and low Y and Yb contents）, high oxygen fugacity, and copper mineralization of the Shilu intrusion, it was most likely formed by partial melting of a subducted young oceanic slab. Whole-rock Sr–Nd isotope-, zircon Hf isotope-, and whole-rock trace element analyses show that Shilu adakitic magmas may have interacted with type II enriched mantle and/or crustal materials during ascent. South China was affected by the Pacific tectonic regime to the east and the Neo-Tethys tectonic regime to the south in the Cretaceous. Based on the Pacific Plate drifting and rotation history, it is hard to explain how the Pacific Plate would have subducted and melted, forming adakitic rocks in the Shilu region. Considering the tectonic history of Southeast Asia and the South China Sea, the Neo-Tethys trench should have been much closer to the South China Block in the Cretaceous, and thus have had a greater impact on the South China Block. Based on the subduction direction, time of subduction,and distance between the Neo-Tethys subduction zone and the Shilu deposit, subduction of the Neo-Tethys ridge is the best mechanism for explaining the Shilu adakitic rocks and Cu–Mo mineralization.

An improved analytical method to determine the content of 52 major, minor and trace elements in marine geological samples, using a HF-HCl-HNO_3 acid system with a high-pressure closed digestion method（HPCD）, is studied by an inductively coupled plasma optical emission spectrometry（ICP-OES） and an inductively coupled plasma mass spectrometry（ICP-MS）. The operating parameters of the instruments are optimized, and the optimal analytical parameters are determined. The influences of optical spectrum and mass spectrum interferences, digestion methods and acid systems on the analytical results are investigated. The optimal spectral lines and isotopes are chosen, and internal standard element of rhodium is selected to compensate for matrix effects and analytical signals drifting. Compared with the methods of an electric heating plate digestion and a microwave digestion, a high-pressure closed digestion method is optimized with less acid, complete digestion,less damage for digestion process. The marine geological samples are dissolved completely by a HF-HCl-HNO_3 system, the relative error（RE） for the analytical results are all less than 6.0%. The method detection limits are 2–40μg/g by the ICP-OES, and 6–80 ng/g by ICP-MS. The methods are used to determine the marine sediment reference materials（GBW07309, GBW07311, GBW07313）, rock reference materials（GBW07103, GBW07104,GBW07105）, and cobalt-rich crust reference materials（GBW07337, GBW07338, GBW07339）, the obtained analytical results are in agreement with the certified values, and both of the relative standard deviation（RSD） and the relative error（RE） are less than 6.0%. The analytical method meets the requirements for determining 52 elements contents of bulk marine geological samples.

The biodistribution of gold nanoparticles （AuNPs） is closely related to toxicological effects and is of great concern because of their potential application in diverse biomedical areas. However, with the discovery of novel anatomic and histological structures for fluid transport, the underlying mechanisms involved in the in vivo transport and biodistribution of AuNPs require further in-depth investigations. In the current study, we investigated the biodistribution of 10-nm AuNPs in rats after intervaginal space injection （ISI） in the tarsal tunnel, where a focal point of tendons, vessels, and nerve fibers may optimally connect to other remote connective tissues. The intravenous injection （IVI） of AuNPs served as a control. The blood and organs were collected at 5, 15, and 30 min and at 1, 4, 12, and 24 h after injection for quantitative analysis of Au distribution with inductively coupled plasma mass spectrometry （ICP-MS）. IVI and ISI yielded significantly different results： The AuNP content in the blood after ISI was much lower than that after IVI; was similar in the lungs, heart, and intestines; and was higher in the skin and muscle. These findings were supported by the ratios of AuNP content and relative organ AuNP distribution proportions. Our results demonstrated a fast, direct, and the circulation-independent AuNP-organ transport pathway, which may improve our understanding of physiological and pathological biodistribution processes in biological systems. Furthermore, these results provide novel insights into the in vivo transport and biodistribution of AuNPs, which may lead to novel and efficient therapeutic and administration strategies.

We collected eleven bench samples of No. 6 coal from the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China, and four samples from the affiliated coal preparation plant. Based on these samples, we used inductively coupled-plasma mass spectroscopy, X-ray diffraction, scanning electron microscope with an energy-dispersive X-ray spectrometer techniques, and borehole exploration data, to investigate the distribution, occurrence and enrichment causes of gallium （Ga） in the coals. Our results show： （1） Gallium is significantly enriched in the coal seams from the study area, with an average content of 18.8-26.0 ppm. Gallium is distributed heterogeneously in the coals, and reaches ore-forming scales only in No. 6 coal of Heidaigou Surface Mine, not in the other mining districts of Jungar Coalfield. （2） On the horizontal plane, Ga is enriched in the main minable coals from the northern and middle part of the coalfield. In the vertical profile, Ga content in the coal seams is higher at the base of Taiyuan Formation （Nos. 8 and 9） and Shanxi Formation （Nos. 3 and 4） than at the top of the Taiyuan Formation. Within the identical coal seam, Ga content is higher in the benches near the roof and floor than in the middle section. （3） Gallium in the coals is associated mainly with kaolinite and boehmite. Additionally, Ga may be adsorbed to some extent by humic acid, resulting in a high level in weathering coal. （4） Geological factors affect Ga enrichment in coal, such as the prop- erty of parent rocks in the source area, the sedimentary environment, organic matter, structure, and past magmatic hydrothermal activity. Especially, Ga content in parent rocks plays a leading role. （5） The mobility and precipitation of trace elements like Ga are controlled principally by the geochemical behavior of the major element A1. Terrestrial and transgressive environments can cause the precipitation of bauxite, whereas marine-continental depositional environments may cause the separation of Ga from A1. In addition, Ga may migrate in the form of gas tively enriched in high-volatile coal. and may be affected by the ground temperature. Thus, it is relatively enriched in high-volatile coal.

Titanium and its alloys are routinely used as biomedical implants and are usually considered to be corrosion resistant under physiological conditions. However, during inflammation, chemical modifications of the peri-implant environment including acidification occur. In addition certain biomolecules including lipopolysaccharide（LPS）, a component of Gram-negative bacterial cell walls and driver of inflammation have been shown to interact strongly with Ti and modify its corrosion resistance. Gram-negative microbes are abundant in biofilms which form on dental implants. The objective was to investigate the influence of LPS on the corrosion properties of relevant biomedical Ti substrates as a function of environmental acidity. Inductively coupled plasma mass spectrometry was used to quantify Ti dissolution following immersion testing in physiological saline for three common biomedical grades of Ti（ASTM Grade 2, Grade 4 and Grade 5）. Complementary electrochemical tests including anodic and cathodic polarisation experiments and potentiostatic measurements were also conducted. All three Ti alloys were observed to behave similarly and ion release was sensitive to p H of the immersion solution. However, LPS significantly inhibited Ti release under the most acidic conditions（p H 2）, which may develop in localized corrosion sites, but promoted dissolution at p H 4–7, which would be more commonly encountered physiologically.The observed pattern of sensitivity to environmental acidity of the effect of LPS on Ti corrosion has not previously been reported. LPS is found extensively on the surfaces of skin and mucosal penetrating Ti implants and the findings are therefore relevant when considering the chemical stability of Ti implant surfaces in vivo.

Aim： Depression is a risk factor for impaired bone mass and micro-architecture, but several antidepressants were found to increase the incidence of osteoporotic fractures. In the present study we used ovariectomized （OVX） rats as a model of osteoporosis to investigate the effects of the antidepressant bupropion on the femoral bones. Methods： OVX animals were treated with bupropion （30, 60 mg-kg-1~d-1） for six weeks. Bone turnover biomarkers （urinary DPD/Cr ratio, serum BALP, OC, TRAcP 5b, CTX and sRANKL levels） and inflammatory cytokines （TNF-a, IL-1β and IL-6） were determined using ELISA. Inductively coupled plasma mass spectroscopy （ICP-MS） was used to determine the femoral bone mineral concentrations. The cortical and trabecular morphometric parameters of femoral bones were determined using micro-CT scan and histopathology. Results： In OVX rats, the levels of bone turnover biomarkers and inflammatory cytokines were significantly elevated and femoral bone Ca2＋ and P043- concentrations were significantly reduced. Moreover, cortical and trabecular morphometric parameters and histopathology of femoral bones were severely altered by ovariectomy. Bupropion dose-dependently inhibited the increases in bone turnover biomarkers and inflammatory cytokines. OVX rats treated with the high dose of bupropion showed normal mineral concentrations in femoral bones. The altered morphometric parameters and histopathology of femoral bones were markedly attenuated by the treatment. Conclusion： Bupropion exerts osteo-protective action in OVX rats through suppressing osteoclastogenesis-inducing factors and inflammation, which stabilize the osteoclasts and decrease bone matrix degradation or resorption.