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Diaryldithiocarbamate complexes, [Fe(S[sub.2]CNAr[sub.2])[sub.3]], have been prepared and their structure, reactivity, and thermal degradation to afford iron sulfide nanomaterials have been investigated. The addition of three equivalents of LiS[sub.2]CNAr[sub.2] to FeCl[sub.2]·4H[sub.2]O in water-air affords dark red [Fe(S[sub.2]CNAr[sub.2])[sub.3]] in high yields. All show magnetic measurements consistent with a predominantly high-spin electronic arrangement at room temperature. The molecular structure of [FeS[sub.2]C(N-p-MeOC[sub.6]H[sub.4])[sub.2][sub.3]] reveals the expected distorted octahedral geometry, but Fe-S distances are more consistent with a low-spin electronic configuration, likely a result of the low temperature (120 K) of the data collection. The thermal stability of [FeS[sub.2]C(N-p-MeC[sub.6]H[sub.4])[sub.2][sub.3]] has been investigated. TGA shows that it begins to decompose at a significantly lower temperature (ca. 160 °C) than previously observed for [Fe(S[sub.2]CNEt[sub.2])[sub.3]], and this is further lowered (to ca. 100 °C) in oleylamine. The decomposition of [FeS[sub.2]C(N-p-MeC[sub.6]H[sub.4])[sub.2][sub.3]] in oleylamine, via either a heat-up or hot injection process, affords nanoparticles of Fe[sub.3]S[sub.4] (greigite), while in contrast, dry heating at 450 °C affords FeS (troilite) as large agglomerates.

The extent to which sulfur dissolves in silicate melts saturated in an immiscible sulfide phase is a fundamental question in igneous petrology and plays a primary role in the generation of magmatic ore deposits, volcanic degassing, and planetary differentiation. In igneous systems, sulfide melts can be described as FeS-NiS-CuS0.5 solutions with Fe/(Fe+Ni+Cu) significantly less than 1. Despite the presence of Ni and Cu in the sulfide, however, most experimental studies to date have concentrated on the effects of silicate melt composition on sulfur solubility and have used essentially pure FeS as the sulfide liquid. We have carried out 49 new experiments at pressures of 1.5-24 GPa and temperatures of 1400 to 2160 °C to investigate the effects of sulfide composition on sulfur solubility as well as extending the pressure and temperature ranges of the available data on sulfide saturation. We find that in the compositional range of most igneous sulfide melts [Fe/(Fe+Ni+Cu) > 0.6] sulfur solubility decreases linearly with Fe content such that at Fe/(Fe+Ni+Cu) of 0.6 the sulfur content at saturation is 0.6 times the value at pure FeS saturation. At lower values of Fe/(Fe+Ni+Cu), however, deviations from this ideal solution relationship need to be taken into consideration. We have treated these non-idealities by assuming that FeS-NiS-CuS0.5 liquids approximate ternary regular solutions.We have fitted our data, together with data from the literature (392 in total), to equations incorporating the effects of silicate melt composition, sulfide liquid composition, and pressure on the solubility of sulfur at sulfide saturation ([S]SCSS). The temperature dependence of [S]SCSS was assumed either to be an unknown or was taken from 1 bar thermodynamic data. The most important best-fit silicate melt compositional term reflects the strongly positive dependence of [S]SCSS on the FeO content of the silicate melt. The best-fit value of this parameter is essentially independent of our assumptions about temperature dependence of [S]SCSS or the solution properties of the sulfide. All natural compositions considered here exhibit positive dependences of [S]SCSS on temperature and negative dependences on pressure, in accord with previous studies using smaller data sets.

Hydrogen sulfide is a highly toxic gas—second only to carbon monoxide as a cause of inhalational deaths. Its mechanism of toxicity is only partially known and no specific therapy exists for sulfide poisoning. We show in several cell types, including human inducible pluripotent stem cell (hiPSC)-derived neurons, that sulfide inhibited complex IV of the mitochondrial respiratory chain and induced apoptosis. Sulfide increased hydroxyl radical production in isolated mouse heart mitochondria and F 2 -isoprostanes in brains and hearts of mice. The vitamin B 12 analog cobinamide reversed the cellular toxicity of sulfide and rescued Drosophila melanogaster and mice from lethal exposures of hydrogen sulfide gas. Cobinamide worked through two distinct mechanisms: direct reversal of complex IV inhibition and neutralization of sulfide-generated reactive oxygen species. We conclude that sulfide produces a high degree of oxidative stress in cells and tissues and that cobinamide has promise as a first specific treatment for sulfide poisoning.

To develop novel inorganic red pigments without harmful elements, we focused on the band structure of Ca[sub.2](Mg, Co)WO[sub.6] and attempted to narrow its bandgap by replacing the W[sup.6+] sites in the host structure of Mo[sup.6+]. Ca[sub.2]Mg[sub.1−x]CoxW[sub.1−y]MoyO[sub.6] (0.10 ≤ x ≤ 0.30; 0.45 ≤ y ≤ 0.60) samples were synthesized by a sol-gel method using citric acids, and the crystal structure, optical properties, and color of the samples were characterized. The Ca[sub.2]Mg[sub.1−x]CoxW[sub.1−y]MoyO[sub.6] solid solution was successfully formed, which absorbed visible light at wavelengths below 600 nm. In addition, the absorption wavelength shifted to longer wavelengths with increasing Mo[sup.6+] content. This is because a new conduction band composed of a Co[sub.3d]-W[sub.5d]-Mo[sub.4d] hybrid orbital was formed by Mo[sup.6+] doping to reduce the bandgap energy. Thus, the color of the samples gradually changed from pale orange to dark red, with a hue angle (h°) of less than 35°. Based on the above results, the optical absorption wavelength of the Ca[sub.2]Mg[sub.1−x]CoxW[sub.1−y]MoyO[sub.6] system can be controlled to change the color by adjusting the bandgap energy.

With the rapid development of nanotechnology, metal sulfide nanoparticles have been widely detected in the environment including water, soils and sediments. Metal sulfides are considered as stable species in the environment, while transformation and risk of nanoparticles have attracted increasing attention due to their specific physicochemical properties compared to bulk materials. Here we review aggregation, sedimentation, chemical and biological transformations, and potential risk of silver sulfide (Ag2S), zinc sulfide (ZnS), copper sulfide (CuS), cadmium sulfide (CdS) and lead sulfide nanoparticles, and quantum dots such as ZnS and CdS. The review shows that both stability and risk of metal sulfide nanoparticles are highly dependent on environmental factors such as pH, inorganic salts and natural organic matter.

The active center for the adsorption and activation of carbon dioxide plays a vital role in the conversion and product selectivity of photocatalytic CO 2 reduction. Here, we find multiple metal sulfides CuInSnS 4 octahedral nanocrystal with exposed (1 1 1) plane for the selectively photocatalytic CO 2 reduction to methane. Still, the product is switched to carbon monoxide on the corresponding individual metal sulfides In 2 S 3 , SnS 2 , and Cu 2 S. Unlike the common metal or defects as active sites, the non-metal sulfur atom in CuInSnS 4 is revealed to be the adsorption center for responding to the selectivity of CH 4 products. The carbon atom of CO 2 adsorbed on the electron-poor sulfur atom of CuInSnS 4 is favorable for stabilizing the intermediates and thus promotes the conversion of CO 2 to CH 4 . Both the activity and selectivity of CH 4 products over the pristine CuInSnS 4 nanocrystal can be further improved by the modification of with various co-catalysts to enhance the separation of the photogenerated charge carrier. This work provides a non-metal active site to determine the conversion and selectivity of photocatalytic CO 2 reduction. The product selectivity of photocatalytic carbon dioxide reduction from carbon monoxide to methane is determined by the active center from metal to sulfur site in metal sulfides. Non-metal sulfur in CuInSnS4 octahedral nanocrystal acts as carbon dioxide activation center for switching selectivity to methane.

Sulphoraphane originates from glucoraphanin in broccoli and is associated with anti-cancer effects. A preclinical study suggested that daily consumption of broccoli may increase the production of sulphoraphane and sulphoraphane metabolites available for absorption. The objective of this study was to determine whether daily broccoli consumption alters the absorption and metabolism of isothiocyanates derived from broccoli glucosinolates. We conducted a randomised cross-over human study (n 18) balanced for BMI and glutathione S-transferase μ 1 (GSTM1) genotype in which subjects consumed a control diet with no broccoli (NB) for 16 d or the same diet with 200 g of cooked broccoli and 20 g of raw daikon radish daily for 15 d (daily broccoli, DB) and 100 g of broccoli and 10 g of daikon radish on day 16. On day 17, all subjects consumed a meal of 200 g of broccoli and 20 g of daikon radish. Plasma and urine were collected for 24 h and analysed for sulphoraphane and metabolites of sulphoraphane and erucin by triple quadrupole tandem MS. For subjects with BMI >26 kg/m2 (median), plasma AUC and urinary excretion rates of total metabolites were higher on the NB diet than on the DB diet, whereas for subjects with BMI <26 kg/m2, plasma AUC and urinary excretion rates were higher on the DB diet than on the NB diet. Daily consumption of broccoli interacted with BMI but not GSTM1 genotype to affect plasma concentrations and urinary excretion of glucosinolate-derived compounds believed to confer protection against cancer. This trial was registered as NCT02346812.

Pancreatic cancer statistics are dismal, with a 5-year survival of less than 10%, and more than 50% of patients presenting with metastatic disease. Metabolic reprogramming is an emerging hallmark of pancreatic adenocarcinoma. CPI-613 is a novel anticancer agent that selectively targets the altered form of mitochondrial energy metabolism in tumour cells, causing changes in mitochondrial enzyme activities and redox status that lead to apoptosis, necrosis, and autophagy of tumour cells. We aimed to establish the maximum tolerated dose of CPI-613 when used in combination with modified FOLFIRINOX chemotherapy (comprising oxaliplatin, leucovorin, irinotecan, and fluorouracil) in patients with metastatic pancreatic cancer. In this single-centre, open-label, dose-escalation phase 1 trial, we recruited adult patients (aged ≥18 years) with newly diagnosed metastatic pancreatic adenocarcinoma from the Comprehensive Cancer Center of Wake Forest Baptist Medical Center (Winston-Salem, NC, USA). Patients had good bone marrow, liver and kidney function, and good performance status (Eastern Cooperative Oncology Group [ECOG] performance status 0–1). We studied CPI-613 in combination with modified FOLFIRINOX (oxaliplatin at 65 mg/m2, leucovorin at 400 mg/m2, irinotecan at 140 mg/m2, and fluorouracil 400 mg/m2 bolus followed by 2400 mg/m2 over 46 h). We applied a two-stage dose-escalation scheme (single patient and traditional 3+3 design). In the single-patient stage, one patient was accrued per dose level. The starting dose of CPI-613 was 500 mg/m2 per day; the dose level was then escalated by doubling the previous dose if there were no adverse events worse than grade 2 within 4 weeks attributed as probably or definitely related to CPI-613. The traditional 3+3 dose-escalation stage was triggered if toxic effects attributed as probably or definitely related to CPI-613 were grade 2 or worse. The dose level for CPI-613 for the first cohort in the traditional dose-escalation stage was the same as that used in the last cohort of the single-patient dose-escalation stage. The primary objective was to establish the maximum tolerated dose of CPI-613 (as assessed by dose-limiting toxicities). This trial is registered with ClinicalTrials.gov, number NCT01835041, and is closed to recruitment. Between April 22, 2013, and Jan 8, 2016, we enrolled 20 patients. The maximum tolerated dose of CPI-613 was 500 mg/m2. The median number of treatment cycles given at the maximum tolerated dose was 11 (IQR 4–19). Median follow-up of the 18 patients treated at the maximum tolerated dose was 378 days (IQR 250–602). Two patients enrolled at a higher dose of 1000 mg/m2, and both had a dose-limiting toxicity. Two unexpected serious adverse events occurred, both for the first patient enrolled. Expected serious adverse events were: thrombocytopenia, anaemia, and lymphopenia (all for patient number 2; anaemia and lymphopenia were dose-limiting toxicities); hyperglycaemia (in patient number 7); hypokalaemia, hypoalbuminaemia, and sepsis (patient number 11); and neutropenia (patient number 20). No deaths due to adverse events were reported. For the 18 patients given the maximum tolerated dose, the most common grade 3–4 non-haematological adverse events were hyperglycaemia (ten [55%] patients), hypokalaemia (six [33%]), peripheral sensory neuropathy (five [28%]), diarrhoea (five [28%]), and abdominal pain (four [22%]). The most common grade 3–4 haematological adverse events were neutropenia (five [28%] of 18 patients), lymphopenia (five [28%]), anaemia (four [22%], and thrombocytopenia in three [17%]). Sensory neuropathy (all grade 1–3) was recorded in 17 (94%) of the 18 patients and was managed with dose de-escalation or discontinuation per standard of care. No patients died while on active treatment; 11 study participants died, with cause of death as terminal pancreatic cancer. Of the 18 patients given the maximum tolerated dose, 11 (61%) achieved an objective (complete or partial) response. A maximum tolerated dose of CPI-613 was established at 500 mg/m2 when used in combination with modified FOLFIRINOX in patients with metastatic pancreatic cancer. The findings of clinical activity will require validation in a phase 2 trial. Comprehensive Cancer Center of Wake Forest Baptist Medical Center.

Hydrogen production from seawater remains challenging due to the deactivation of the hydrogen evolution reaction (HER) electrode under high current density. To overcome the activity-stability trade-offs in transition-metal sulfides, we propose a strategy to engineer sulfur migration by constructing a nickel-cobalt sulfides heterostructure with nitrogen-doped carbon shell encapsulation (CN@NiCoS) electrocatalyst. State-of-the-art ex situ / in situ characterizations and density functional theory calculations reveal the restructuring of the CN@NiCoS interface, clearly identifying dynamic sulfur migration. The NiCoS heterostructure stimulates sulfur migration by creating sulfur vacancies at the Ni 3 S 2 -Co 9 S 8 heterointerface, while the migrated sulfur atoms are subsequently captured by the CN shell via strong C-S bond, preventing sulfide dissolution into alkaline electrolyte. Remarkably, the dynamically formed sulfur-doped CN shell and sulfur vacancies pairing sites significantly enhances HER activity by altering the d -band center near Fermi level, resulting in a low overpotential of 4.6 and 8 mV at 10 mA cm −2 in alkaline freshwater and seawater media, and long-term stability up to 1000 h. This work thus provides a guidance for the design of high-performance HER electrocatalyst by engineering interfacial atomic migration. Stable and efficient hydrogen production from seawater remains challenging. Here the authors engineer sulfur migration in NiCoS electrocatalyst via N-doped carbon encapsulation, generating S vacancies and S doped CN active sites at the interface that improves electrocatalytic hydrogen evolution activity and durability in both alkaline freshwater and seawater.

Growth media have been developed to facilitate the enrichment and isolation of acidophilic and acid-tolerant sulfate-reducing bacteria (aSRB) from environmental and industrial samples, and to allow their cultivation in vitro. The main features of the ‘standard’ solid and liquid devised media are as follows: (i) use of glycerol rather than an aliphatic acid as electron donor; (ii) inclusion of stoichiometric concentrations of zinc ions to both buffer pH and to convert potentially harmful hydrogen sulphide produced by the aSRB to insoluble zinc sulphide; (iii) inclusion of Acidocella aromatica (an heterotrophic acidophile that does not metabolize glycerol or yeast extract) in the gel underlayer of double layered (overlay) solid media, to remove acetic acid produced by aSRB that incompletely oxidize glycerol and also aliphatic acids (mostly pyruvic) released by acid hydrolysis of the gelling agent used (agarose). Colonies of aSRB are readily distinguished from those of other anaerobes due to their deposition and accumulation of metal sulphide precipitates. Data presented illustrate the effectiveness of the overlay solid media described for isolating aSRB from acidic anaerobic sediments and low pH sulfidogenic bioreactors. The paper describes how bacteria that live in acidic environments, and that form hydrogen sulphide from sulfate, may be isolated and grown in the laboratory. Graphical Abstract Figure. The paper describes how bacteria that live in acidic environments, and that form hydrogen sulphide from sulfate, may be isolated and grown in the laboratory.