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Currently, researchers have indicated that inorganic minerals in reservoirs, such as clay minerals, carbonates and quartz, can catalyze the evolution of organic matter into oil and gas. Therefore it is reasonable to believe that the minerals in reservoirs may act as a catalyst support with the metal-containing catalyst added fromoutside during the thermal recovery of heavy oil. This paper studied the aquathermolysis of heavy oil catalyzed by minerals and transition metal. The reaction conditions of two heavy oil samples were investigated. The results show that the optimal reaction conditions of heavy oil fromXinjiang BaikouquanOilfield (XBO) are the reaction temperature of 250 °C and the reaction time of 6 h; for the crude oil from Xinjiang Tahe Oilfield (XTO), the optimal reaction conditions are determined to be the reaction temperature of 250 °C and the reaction time of 12 h, the water-oil ratio of the two oils is 0.3.Under optimal conditions, viscosity and pour point of heavy oil are significantly reduced. Differential scanning calorimetry (DSC), GC-MS analysis, thermogravimetric analysis (TGA), and elemental analysis were used to study the properties of the two heavy oil samples before and after reaction to explore themechanism of the catalyzed aquathermolysis of heavy oil. This work will benefit the related heavy oil recovery work in this field. [ABSTRACT FROM AUTHOR]

NiO-based catalysts are among the most active and selective catalytic systems for lowtemperature oxidative dehydrogenation (ODH) of ethane into ethylene and, therefore, they have been extensively studied in the last twenty-five years. This paper reviews the most relevant works focusing on NiO-based catalysts for ethane ODH, including promoted and unpromoted, bulk and supported NiO. The effects of the nature of the promoter and of the support together with the influence of the method of preparation used on their activity in ethane ODH are discussed in detail as they were shown to be key factors controlling the catalytic performance, including the catalyst stability. The reaction mechanism involved in ethane ODH reaction over NiO-based catalysts is also presented and discussed. [ABSTRACT FROM AUTHOR]

The SCR-DeNOx commercial catalysts are reported as possible candidates to remove aromatic VOCs and NOx simultaneously. In this paper, we present the kinetic studies of the oxidation of benzene and its mono-halogenated derivatives over V2O5-WO3/TiO2 catalyst as typical high-dust SCR-DeNOx system. The kinetic investigation follows the influence of temperature on the conversion of aromatic VOCs to establish the apparent energy activation and dependence on between temperature and the effective constant rate of the catalytic oxidation reaction. The data shows that the catalytic oxidation process takes place after a combined kinetic mechanism, mass transport through pores--chemical transformation. [ABSTRACT FROM AUTHOR]

Most papers on kidney stones arising from infection concentrate on the mineral struvite. In this contribution, we would like to call attention to other mineral phases such as highly carbonated calcium phosphate apatite, ammonium urate, and whitlockite, by presenting clinical and chemical data. We start with epidemiological data which emphasize the increase in the prevalence of kidney stones related to infection. Then we present a statistical analysis of more than 85,000 stones which have been analysed at the Laboratoire des Lithiases of Assistance Publique-Hôpitaux de Paris which gives insights regarding the link between urinary tract infection and struvite, carbonated calcium phosphate apatite (carbapatite), and also surprisingly whitlockite. Some information regarding the pathogenesis of kidney stones linked to infection, the nature of the bacteria which have been identified, and the approach to precisely analyse infrared spectra to identify struvite, carbapatite, and whitlockite, conclude this first part. To complete this clinical description, we describe the crystallographic structure and the chemistry of three relevant compounds namely carbonated calcium phosphate, struvite, and whitlockite. To conclude this second part, the dependence of crystallite morphology of struvite on pH and on the presence, or absence, of bacteria, is described. Based on clinical and chemical data, it is becoming clear that struvite is not the only mineral intimately related to renal infectious processes, but that whitlockite and carbapatite with a high carbonation rate are strongly associated with urinary tract infection as well. [ABSTRACT FROM AUTHOR]

It is a matter of strategic independence for many countries to urgently find processes that take into account environmental and economic issues when recycling critical metals. Liquid--liquid (L/L) extraction is a promising method for recovering rare-earth elements from electrical and electronic waste. However, an optimized process on an industrial scale has not yet been established. One of the main reasons is the lack of fundamental knowledge. Therefore, designing a cost-effective and adaptive formulation is still beyond the scope of possibilities. This requires deciphering the molecular forces that control ion transfer beyond the classical supramolecular complexation and developing predictive models compatible with the design and control needs of recycling processes. In all liquid/liquid processes, the high loading of the organic solvent with metal salts/acids or extractant can sometimes lead to a third phase formation. Phase modifiers are often added to the solvent phase in order to prevent the formation of this third phase. However, the effect of these additives on the extraction efficiency as well as their mechanisms of action are still poorly understood. The phase modifiers used in industrial processes are mainly fatty alcohols, called "lipotropes". In this paper, we study a new class of molecules opening new possibilities beyond the commonly used phase modifiers (i.e., n-octanol). These are the "hydrotropic" molecules. We first show the role of a model hydrotrope (PnP) in preventing the third phase formation for different extraction systems. We also show that the role of modifiers can be understood according to three molecular mechanisms: as co-solvent, as co-surfactant and by preferential solvation. The dominant molecular effect can be identified and quantified by combining surface tension and neutron scattering experiments. In the case of phase modifiers that are hydrotropes, the co-solvent or co-surfactant effect is dominant. In the case of "lipotropes", the preferential solvation mechanism is emphasized. Finally, the consequences of these mechanisms on the extraction efficiency and selectivity are discussed. [ABSTRACT FROM AUTHOR]

The California State Parks curators granted access to artifacts owned by Jack London that are in storage in their Sonoma Barracks in Sonoma, CA. A medicine case, drug vials, and various paper documents that covered the period of his life from 1906 to 1915 were examined for drug residues left on their surface. All the objects were tested with the non-invasive surface analysis EVA (ethylene-vinyl acetate) technology, which consist of a foil studded with ground mixed-bed cation/anion exchangers as well as with C8 and C18 resins. The harvested material collected by the foils was analysed via GC-MS and the following 12 drugs were identified: N-(4-ethoxyphenyl) acetamide, phenyl salicylic acid, morphine, 6-monoacetylmorphine, 3-acetylmorphine, diacetylmorphine, dipenteneglycol, quinine dihydrochloride, quinine base, atropine, scopolamine and hyoscyamine. Despite the claims by his biographers that he used opium, morphine, and heroin on a regular basis this assertion could not be confirmed by the chemical analyses of the objects here tested. Only two opioids were discovered, morphine and diacetylmorphine (heroin) both of which could have been derived from the use of common, legal (over-the-counter) flu and cough medications. [ABSTRACT FROM AUTHOR]

This document is a special issue of the journal Comptes Rendus Chimie, focusing on women chemists in France in 2024. The guest editor for this issue is Janine Cossy, a renowned chemist who has made significant contributions to the field. Cossy's research primarily focuses on the synthesis of natural products and biologically active molecules, as well as the development of selective synthetic methods. She has published over 560 papers and holds 18 patents. Cossy is also a member of prestigious scientific academies and serves as an associate editor for several chemistry journals. [Extracted from the article]

In this paper, catalytic hydro-deoxygenation (HDO) of bio-oil’s model molecules (acetic acid, 4-ethylguaiacol, and furfural) using Ni2P/HZSM-5 catalyst was carried out to better identify the products and make the modeling work of HDO process more reliable. Results showed that low temperatures favored the formation of acetaldehyde and acetone during acetic acid HDO, but disfavored the formation of aromatic hydrocarbons. Acetone was produced via the self-ketonization reaction of acetic acid. In most cases of 4-ethylguaiacol HDO, phenol, cresol, and 2, 4-dimethylphenol were the primary products. For furfural HDO, the major furan and CO products proved that the direct decarbonylation of furfural was the main reaction. Accordingly, the main pathways of acetic acid, 4- ethylguaiacol, and furfural HDO were proposed, which could provide significant guidance for the upgrading of crude bio-oil. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide and peroxymonocarbonate anion-based bleach reactions are important for many applications such as paper bleach, waste water treatment and laundry. Nonheme iron(III) complexes, [FeIII(L1¡4)Cl2] with the 1,3-bis(20-Ar-imino)isoindolines ligands (HLn, n Æ1--4, Ar Æ pyridyl, thiazolyl, benzimidazolyl and N-methylbenzimidazolyl, respectively) have been shown to catalyze the oxidative degradation of morin as a soluble model of a bleachable stain by H2O2 in buffered aqueous solution. In these experiments the bleaching activity of the catalysts was significantly influenced by the Lewis acidity and redox properties of the metal centers, and showed a linear correlation with the FeIII/FeII redox potentials (in the range of 197--415 mV) controlled by the modification of the electron donor properties of the ligand introducing various aryl groups on the bisiminoisoindoline moiety. A similar trend but with low yields was observed for the disproportionation ofH2O2 (catalase-like reaction) which is a major side reaction of catalytic bleach with transitionmetal complexes. The effect of bicarbonate ions might be explained by the reduction of Fe(III) ions and/or the formation of peroxymonocarbonate monoanion, which is a much stronger oxidant and could increase the formation of the catalytically active high-valent oxoiron species. [ABSTRACT FROM AUTHOR]

The filtration properties in solid--liquid separation mainly depend upon the filter cake properties, for instance, cake resistance. However, particle size distribution, particle shape, and their arrangements significantly impact cake filtration. This paper aims to review the work done so far and collate both fundamental and applied work with regard to the quantification of cake properties. The cake resistance and cake porosity in terms of shape, as well as varying particle size distribution width, are discussed here. This work summarizes the current state of the technology and recommends advancements and improvements for future research. [ABSTRACT FROM AUTHOR]

The rejection of anti-inflammatory drugs by membranes has shown paramount importance in separation membrane processes such as nanofiltration and reverse osmosis (NF/RO) membranes for pharmaceutical industries. Therefore, the main objective of this paper is to use support vector machine (SVM) and artificial neural network (ANN) to model the rejections of anti-inflammatory drugs by NF/RO membranes using 300 experimental data points gathered from the literature. Both approaches (ANN and SVM) gave close results with a slight superiority of the neural networks model demonstrated by its correlation coefficient (R) and root mean square error (RMSE) values of 0.9930 and 1.8094% respectively, in contrast to 0.9900 and 2.2355% for SVM. Sensitivity analysis by the weight method demonstrates that the most relevant variables that influence the rejection of antiinflammatory drugs are: effective diameter of an organic compound in water "dc ", molecular length, contact angle, and zeta potential. These input relevant variables have a significant contribution (relative importance superior to 10%). [ABSTRACT FROM AUTHOR]

Praziquantel and Syloid 244 FP (amorphous silicon dioxide) were ground in a vibrational mill in standard conditions (150 or 300 at 25 Hz). Amorphous solid dispersions were obtained in a very short grinding time (15 min), as testified by DSC, PXRD and ESEM analyses. Samples ground at 150 and 300 showed the presence of the same degradation product, as was evident from UPLC, MS and NMR analyses. This short paper brings to light the tremendous lattice de-structuration ability of Syloid 244 FP upon grinding toward Praziquantel as well as its detrimental influence on promoting chemical degradation through ring opening and oxidation. [ABSTRACT FROM AUTHOR]

This paper deals with the electrochemical properties of three iso-structural compounds of general formula [SiW10 O36(M2O2E2)]6¡ (M Æ Mo or W; E Æ S or O). A first part is focused on their electrochemical behaviors in aqueous medium. A second part concerns the electrocatalytic properties of these compounds in aqueous medium and the preparation of modified glassy carbon electrodes through a layer-by-layer methodology. Thismethod allowed preparing a multilayer system, which was applied to the electroanalysis of iodate anions in aqueousmedium with a limit detection of 6.2M. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the simultaneous adsorption of basic red 2 (BR2) and basic violet 3 (BV3) in a binary system in a batch mode using date stones as low cost adsorbents. For both dyes, experimental kinetic data were well fitted by the Brouers–Sotolongo model (R2 R² = 0.99) and intraparticle diffusion was the controlling step in mass transfer mechanisms. The intraparticle diffusion extent was found to be lower for BR2 (1.13×10-11 cm²/s) than for BV3 (1.11×10-11 cm²/s) when compared to individual solutions (1.24×10-10 cm²/s and 1.76×10-11 cm²/s for BR2 and BV3, respectively). The equilibrium study revealed lower adsorption capacities (41.95 and 88.91 mg/g for BR2 and BV3, respectively) compared to the individual sorption results (92.00 and 136.00 mg/g for BR2 and BV3, respectively) for both dyes. To assess the extent of competition and the preference of dyes for functional sites, competition and separation factors were calculated suggesting an antagonistic effect as well as a greater affinity for BV3 than for BR2 to the adsorption sites. The equilibrium adsorption results were best fitted by modified Langmuir and P-factor Langmuir isotherms for BR2 and BV3, respectively. Besides, based on enthalpy values (16.30 and 30.26 kJ/mol for BR2 and BV3, respectively), the simultaneous adsorption of both dyes was endothermic while the entropy revealed a higher affinity of the investigated adsorbent to BV3. The sorption process in separate systems (BR2 and BV3) was thermodynamically feasible for both dyes with negative free enthalpy values. The comparison to single systems showed an increase of affinity for BV3 contrarily to BR2 and, a decrease of spontaneity with higher extent for BR2. [ABSTRACT FROM AUTHOR]

This paper focuses on the synthesis of a new silver nanocomposite adsorbent derived from rice husk as raw material. The synthesis is based on triethoxysilane chemistry and the reduction of silver without the aid of reductant chemicals. The derived AgNPs@SiO2 nanocomposites are fully characterized and then used for the removal of mercury (II) from aqueous solutions. The results demonstrated that the affinity of the composite for mercury is high and the removal mechanism is adsorption accompanied by a redox reaction between mercury and silver followed by the formation of calomel and amalgams between silver and mercury. The silver--mercury reaction is complex, and its stoichiometry seems to scale with the silver content. Besides the importance of the surface reactions, the successful implementation of biosourced silica for mercury removal from water is useful for the development of strategies for the valorization of agricultural waste and boosts the concept of circular economy and bioeconomy. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims at giving an idea of the contributions to the study of corrosion phenomena ensured by the practice of localized electrochemical techniques. For many corrosion phenomena high resolution is required. This is due to the fact that a huge amount of relevant information about electrochemical processes can be examined at a microscale. The present work is focused both on theoretical and practical aspects of these modern localized electrochemical techniques. In particular Scanning Kelvin Probe (SKP) and Scanning Vibrating Electrode Technique (SVET) will be discussed in detail. Concerning theoretical aspects, this paper summarizes in some fundamental equations the main operating principles behind the two different techniques. The basics of the two equipments are explained in simple terms with the aid of some pictures. Experimental data are also reported, in order to better understand the working principles of these devices and their potential. The novelty of the data obtained with these tools will be highlighted by the discussion of the theoretical principles and the explanation of several examples. [Copyright &y& Elsevier]

Abstract: Attaining novel structures in compounds displaying remarkable properties is the goal of numerous solid-state chemists and physicists. Several approaches for predicting new structures exist but, whatever they are, one of the essential steps is to understand their architecture. It needs to collect the maximum information for deciphering the building code. In this paper, we give a personal account and focus on the powerful synergy of transmission electron microscopy and X-ray diffraction techniques for achieving it. We have chosen the example of the misfit-layered cobaltites, which appear more and more complex as we attain each new level in the hierarchy of their structures. We have limited our illustration to the first period of the misfit cobaltites “research story”, from the discovery of highly complex oxides to the understanding of the architecture building, without reporting on the numerous further papers devoted to iso-structural compounds and to their remarkable properties of thermoelectric power. [Copyright &y& Elsevier]

Abstract: Whatman cellulose impregnated with calcium and magnesium carbonates was oxidized and chemiluminescence accompanying this oxidation has been measured. It was shown that magnesium ions in deacidified cellulose pulp promote the light emission significantly. On the other hand, acid papers give the more pronounced light signals at temperatures close to ambient. The relation between chemiluminescence runs and paper degradation has been implicated, with an attempt to extrapolate half-lives of paper samples to conditions close to ambient. To cite this article: J. Rychlý et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Mn porphyrin provides a possibility to constitute the novel mimic catalyst with peroxidase-like activity. A simple method for preparing a novel catalyst PEI–AuNPs–Mn III PPIX, used in aqueous media, was presented in this paper. The covalent anchoring of Mn III PPIX and PEI were verified, meanwhile gold nanoparticles with the diameter less than 10 nm were dispersed uniformly and stably. The remarkable peroxidase-like catalytic activity of PEI–AuNPs–Mn III PPIX was displayed in the oxidative degradation of azo dye acid orange 7 (AO7) as the model reaction in the presence of trace of H 2 O 2 . The synergistic effects of PEI–AuNPs and Mn III PPIX on the enhancement of catalytic activity were observed at pH 2.0. Possible pathways involving in the formation of active radicals are proposed. The construction of PEI–AuNPs–Mn III PPIX nanocomposite offers a new insight into the application of Mn porphyrin upon activation of H 2 O 2 , which have potential applications in many fields. [ABSTRACT FROM AUTHOR]

Diverse applications of azo dyes in textiles, paper, leather, cosmetics, pharmaceutical, and food industries along with their deleterious impacts on human beings and aquatic life have raised urgent calls for the treatment of effluent containing azo dyes to remove them or convert them into useful and safe products. This inspires us to modulate acid red 37 to acid red Schiff bases (ARSBs), which were further palladinated to yield monopalladated products (Pd(II)-ARSBs) with an emphasis to obtain new pharmacological (antibiotic and anticancer) candidates. These new cyclopalladated complexes were structurally characterized and pharmacologically evaluated as well for their in vitro antimicrobial, against a common panel of pathogenic G + and G − bacterial and fungal strains, and anticancer activities against human breast carcinoma (MCF-7) cell lines. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of an antibiotic (spiramycin) has been studied using immobilized titanium dioxide (TiO 2 ) as a photocatalyst in a laboratory reactor under ultraviolet illumination (365 nm). The degradation of the antibiotic was monitored by ultraviolet spectrophotometry and high-pressure liquid chromatography and confirmed by an antibacterial activity evaluation. Two types of TiO 2 (P25 and PC500) immobilized on glass plates were compared. For TiO 2 PC500 immobilization on glass and paper was also studied. A slightly better degradation was obtained with TiO 2 P25 for which the degradation kinetics were investigated. The Langmuir–Hinshelwood kinetic model is satisfactorily obeyed at initial time and in the course of the reaction. Adsorption and apparent rate constants were determined. These results show a complete degradation of spiramycin, which was confirmed by the inhibition of the antibacterial activity of Staphylococcus xylosus , when exposed to spiramycin solutions treated with photocatalyst for a short time. In addition, the codegradation of spiramycin and tylosin was investigated and showed that tylosin had a higher affinity to the catalyst TiO 2 P25 than spiramycin. The complete degradation of spiramycin confirms the feasibility of such a photocatalytic treatment process for spiramycin elimination from contaminated water. [ABSTRACT FROM AUTHOR]

In this paper, an effective procedure is described for the synthesis of novel indoles containing highly polarized double bonds. The strategy involves the preparation of (indolylmethyl)malononitriles via the one-pot three-component reaction of an aldehyde, malononitrile and indole in the presence of Zn(OAc) 2 /NaOAc under silent and ultrasonic conditions. The reaction further proceeds through oxidative elimination under solvent-free conditions in the presence of Ca(OCl) 2 to furnish indolylacrylonitriles in high yields and short reaction times. [ABSTRACT FROM AUTHOR]

The nanocrystallization of organic pure and composite materials in amounts compatible with industrial demands opens an important challenge as such compounds are of high interest in the fields of pharmacy and defense. We demonstrate the versatility of the Spray Flash Evaporation (SFE) process which is a continuous technique and will establish a wider sphere of hierarchical nanocomposite structures and materials. The paper shows in detail the progress that is reached on the precise nanostructural tuning of composite matter, giving by the same way access to precise medical applications (e.g., advanced drug synthesis). Furthermore, SFE enables the production of energetic nanostructured precursors and therefore permits the synthesis by detonation of ultrafine nanodiamonds with pioneering sizes less than 5 nm. Without any doubt, the use of SFE opens a large fundamental research possibility and applicative issue for future products. To realize opportunities described in the manuscript for the materials conceived by SFE, we also introduce challenges to face in terms of structural characterization with high spatial and chemical resolution that were never reached in a combined manner before. [ABSTRACT FROM AUTHOR]

In this paper, an azo-containing Schiff base complex of manganese [Mn 2+ -azo ligand@APTES-SiO 2 @Fe 3 O 4 ] immobilized on chemically modified Fe 3 O 4 nanoparticles has been used as a magnetically retrievable catalyst for the alcoholysis of different epoxides to their corresponding alkoxy alcohols with methanol, ethanol and n -propanol. The newly magnetic nanoparticles (MNPs) were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and vibrating sample magnetometry (VSM). [ABSTRACT FROM AUTHOR]

This paper focuses on the effect of the La/Co ratio on the structure of alumina cobalt supported catalysts for Fischer–Tropsch synthesis. Catalysts are prepared by wetness impregnation of alumina followed by calcination in air. The catalysts contain 10 wt% of cobalt and between 0 and 20 wt% of La (0, 5, 10, 15, 20). The catalysts were activated by reduction in hydrogen at 673 K and the catalytic performance was evaluated in a fixed bed reactor at 20 bar and 493 K. A wide range of techniques (BET, XRD, TPR, and XPS) were used for catalyst characterization at each preparation step and showed strong impact of the La/Co ratio on the structure, reducibility of supported cobalt phases. It was shown that 10 wt% of lanthanum allows reducing cobalt aluminate and improving catalytic performances. [ABSTRACT FROM AUTHOR]

The article "Guest Editors" is published in the journal Comptes Rendus Chimie and provides information about the guest editors of a special issue on Materials and Clean Processes for Sustainable Energy and Environmental Applications. The guest editors are Dr. Mejdi Jeguirim and Dr. Patrick Dutournié, both professors at the University of Haute-Alsace in France. Dr. Jeguirim specializes in energy, process engineering, and kinetics modeling, while Dr. Dutournié focuses on energy and chemical engineering. They have extensive research experience, have published numerous papers, and are involved in various scientific journals and research programs. The article also mentions their achievements and recognition in their respective fields. [Extracted from the article]

Recent epidemiologic investigations have identified an association between type 2 diabetes and uric acid kidney stones. This association was more apparent in women than in men. In this paper, we show through powder neutron diffraction that particle sizes of uric acid kidney stones were significantly different between male and female patients (84.7 ± 5.3 vs. 140.2 ± 6.7 nm, p = 0.000003). Interestingly, when type 2 diabetes appeared, this structural difference between male and female vanished (76.1 ± 3.9 vs. 78.8 ± 4.2 nm, not significant). Thus, the complete set of structural data is in line with observations regarding epidemiological data. Some explanations based on supersaturation are discussed. [ABSTRACT FROM AUTHOR]

Among the different techniques specific to synchrotron radiation, the combination of X-ray absorption spectroscopy with X-ray scattering experiments is a powerful tool to characterize samples with a capability to gather structural and electronic information at the cellular level. In the present contribution, selected examples making use of such techniques point out as well the information that one can have access to. Via the presentation of the physicochemical data, this paper focuses on displaying the information that has a significant clinical character. [ABSTRACT FROM AUTHOR]

This review paper presents an overview of heterogeneous selective ammoxidation and oxidative dehydrogenation (ODH) of light alkanes, particularly of ethane. The conversion of ethane to ethene is in great demand in the domestic and worldwide chemical industry. The review has been voluntarily restricted to metal oxide-type catalysts, as it is devoted to the special issue honouring Edmond Payen and is based on 30 years of experience and discussions with pioneering scientists in the field. The main key factors, designated by Grasselli as the “7 pillars”, have been emphasised: isolation of active sites, M–O bond strength, crystalline structure, redox features, phase cooperation, multifunctionality and the nature of the surface oxygen species. The main features and physical and chemical properties of solid catalysts for selective oxidation compared to total oxidation have also been emphasised. Several case studies have been presented to illustrate the concept and importance of the key factors of catalyst preparation and activation and of the catalytic atmosphere. Based on such analysis and recent discoveries and process developments perspective views are also given. [ABSTRACT FROM AUTHOR]

Lately, the cosmetic and personal care market has been more and more driven toward natural ingredients by the rising consumers' awareness about personal health and safety and their will for safer cosmetics free of harmful chemicals. Preservatives are no exception to the rule: evidence or suspicion of the toxicity of certain synthetic preservatives that have been around for decades pushed the cosmetic industry forward to seek for natural alternatives, as the selection of natural preservatives already available is quite limited. Sourcing active metabolites and developing new natural ingredients are long-term procedures that are thoroughly described in the present paper, via the example of the design of a natural preservative based on the Santolina chamaecyparissus extract, and of the assessments of its preservative effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, a theoretical study of the molecular properties of NaH⋯2(HF) and NaH⋯4(HF) complexes is reported. Based on MP2/6-311++G(d,p) calculations, the dihydrogen bonds (H⋯H), hydrogen bonds (F⋯H) and halogen-hydride bonds (F⋯Na) of these intermolecular systems were fully characterized. The characterization involved the following procedures: the examination of structural parameters, analysis of vibration modes such as frequencies shifted to red or blue in the infrared spectrum, modeling of the electronic topology, quantification of the cooperative energy followed by charge transfer and, finally, natural bond orbital analysis. The results show short intermolecular distances with high electronic density, while the stretch frequencies of the proton donors and acceptors are unusually shifted, and some values reach 1000 cm −1 . When all subunits of the complexes are taken into account, in this case the NaH and HF molecules, the high value for the strength of the H⋯H dihydrogen bond in NaH⋯2(HF) suggests the formation of an additional subpart, i.e., the H 2 molecule. [ABSTRACT FROM AUTHOR]

Speciation of mercury compounds in environmental and biological samples requires different techniques and different approaches. This speciation is mandatory to explain the toxicity, the reactivity and the bioavailability of mercury. It is dominated by inorganic mercury species Hg(II) and Hg(0), and the organic mercury species CH 3 Hg and (CH 3 ) 2 Hg. In this paper, some aspects of mercury speciation are presented in terms of: - mercury reactivity (Hg(II) complexation and reduction), - mercury species distribution in the main compartments of the environment [ABSTRACT FROM AUTHOR]

This paper describes the design by juxtaposition of anti-infectious moieties, a series of hybrid imidazopyridinyl-arylpropenone compounds. These compounds ( 5a–y ) were synthesized by a crotonization reaction of 1-(2-methylimidazo[1,2- a ]pyridin-3-yl)ethanone ( 3 ) with benzaldehyde derivatives ( 4 ). Spectral determination of structure of those compounds was performed by NMR and ESI mass spectroscopy. From the screening of antiparasitic and antimicrobial activities, the compound 5q (IC 50 = 1.52 μM) was identified for possible development against a chloroquine-resistant strain of Plasmodium falciparum . The compounds 5n, 5s and 5w showed a veterinary interest due to their nematicidal activities (LC 100 ) against Haemonchus contortus from 7.1 to 1.5 nM. Against candidiasis, three other compounds ( 5e, 5g, 5v ) inhibited drug-resistant strains of Candida albicans (MIQ = 1.25 to 0.31 μg). This study showed that the arylpropenone functional group vectorised by imidazopyridine could be considered as a new pharmacophore with potential anti-infectious activities. [ABSTRACT FROM AUTHOR]

This research paper presents a quick and ecofriendly technique for the extraction of harpagoside (HS), the active marker of Harpagophytum procumbens (HP), along with a comparison with conventional methods so as to propose an efficient HPLC method. HP is widely used as an anti-inflammatory in phytotherapy. The quality control of the herbal drug and extract calls for a time consuming method of conventional extraction, which involves a high consumption of solvents. In this study, HP has been extracted using conventional ultrasound (UAE) and microwave (MAE)-assisted methods. The effects have been examined based on several parameters of HS extraction efficiencies. An HPLC method with a core-shell column was developed in order to calculate the HS in HP. The flow rate was reduced by 4. The method of validation used is specific, linear, precise and accurate. MAE and UAE saved solvent consumption, time and energy. It has, therefore, been found that the combined UAE-HPLC process is convenient and appropriate for the quality control of HP. [ABSTRACT FROM AUTHOR]

Methods of Green Chemistry are in the meantime established in process design for extraction of natural products [1] . Moreover, natural products do have the inherent societal benefit of being a priori bio-degradable and therefore do not cause any additional waste-water and recycling problems in hospitals, cities and municipalities or environmental enrichment [2] . Nevertheless, those inherent benefits could be easily compromised if they are not combined with the design and operation of fully integrated processes in manufacturing. One isolated action of Green Chemistry is not sufficient to gain the entrepreneurial balance of economy and ecology with competitive manufacturing, new marketable products, and sustainability. While any process modification could be implemented in substituting simply one existing step, a fully integrated new process needs to be set up to exceed the existing benchmark or best practice and to be transferred into manufacturing. Finding alternative solvents and enhancing mass transfer in extraction need to be integrated. This integration into a complete process from extraction over purification to formulation, considering recycling at all steps, is a complex task which could not be fulfilled on a purely experimental basis. The efforts would be too high and costly. Therefore, the paper reviews the existing status shortly and exemplifies based on a case study, choosing 10-deacetylbaccatin III as a typical example, a theoretical approach in thermodynamics and process modeling, and how they can contribute to an alternative process design. Still, these steps in conceptual process design and basic engineering seem to be the major challenge in industrial acceptance of alternative ideas. The authors have described the transfer into innovative manufacturing concepts already elsewhere [1–3] . [ABSTRACT FROM AUTHOR]

Algerian's municipal sewage treatment plants generate around 10 6 m 3 of sewage sludge annually. Recently, rapid expansion of wastewater treatment plants without equal attention to the treatment of the produced sludge has generated increasing concerns. While the sludge is usually incinerated or used as an agricultural fertilizer and may contain numerous nutrients, there may also be harmful substances that complicate sludge management. Hence the removal of pollutants from the sludge is necessary before further usage. This paper discusses the characteristics of potable water treatment sludge containing a high aluminum content. Furthermore, an electrokinetic treatment is proposed to remove aluminum from this sludge by varying the type of solution contained in the cathode compartment and modifying the treatment time to optimize the efficiency of the process. Successful results were achieved where 60% of aluminum was collected on the cathode side with a consumed energy around of 1000–2000 kWh kg −1 of sludge weight. [ABSTRACT FROM AUTHOR]

Drug delivery systems based on collagen sponges have increasingly become interesting materials for different medical applications. In this paper we present the obtaining, characterization and in vitro release of ibuprofen from collagen-based biomaterials in the form of sponges. The structural and morphological characteristics of these materials were investigated by infrared spectroscopy (FT-IR) and water uptake tests. Collagenase degradation, anti-inflammatory drug release and the kinetic mechanism are also discussed. The results obtained suggest that these new systems based on collagen have good potential for sustained release of analgesic and anti-inflammatory agents such as ibuprofen and the combination of collagen and ibuprofen as a sponge is a promising therapeutic method for the treatment of dental problems. [ABSTRACT FROM AUTHOR]

Zinc oxide has attracted wide research interest due to its unique properties. Its band gap width, high refractive index, high electrical conductivity, and high optical transmission in the visible, etc., have made it suitable for a variety of applications, such as gas sensors, varistors, optoelectronic devices, etc. The first part of the paper presents three methods for the synthesis of zinc oxide nanoparticles: sol–gel, polyol, and hydrothermal methods. Then, we report on the characteristics of the powders in terms of structure, composition and morphology as well as of in-vitro testing on cell cultures. The influence of the nanoparticles on cell viability was evaluated by the lactate dehydrogenase method. It turns out that all ZnO powders tested present high cytotoxicity. Also, it is found that the synthesis method significantly influences cell viability, the lowest one being obtained for nanopowders synthesized by the sol–gel method. [ABSTRACT FROM AUTHOR]

This paper summarizes the main results obtained by the Fuel Combustion Group in three applications: (1) carbon-based catalysts for the selective catalytic reduction (SCR) process of NO x , (2) Pt and Pt–Ru catalysts for direct alcohol fuel cells, (3) carbon-supported catalysts for the electroreduction of CO 2 . Concerning the first aspect, low-cost catalysts able to work at lower temperatures have been prepared and compared with commercial catalysts; for the second one, new catalysts for methanol and ethanol electrochemical oxidation exhibiting current densities that are double those of the commercial ones have been developed; as regards the third one, carbon-supported catalysts for the electroreduction of CO 2 based on Fe and Pd were synthesized and tested. Formic acid was obtained as the main product on all Fe/C electrodes. [ABSTRACT FROM AUTHOR]