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1.
Sci Total Environ ; 926: 172011, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38561128

ABSTRACT

Coal gasification slag (CGS) contains variable amounts of heavy metals, which can negatively impact the environment. The mineral composition, element distribution, occurrence, and leaching characteristics of heavy metals in coal gasification coarse slag (CGCS) and coal gasification fine slag (CGFS) are studied to explain the leaching behavior of heavy metals in CGS. The movable components of heavy metals in CGFS (0.06 %-63.03 %) are significantly higher than those in CGCS (0 %-18.72 %). Leaching Environmental Assessment Framework 1313 data shows that heavy metals Zn, Cr, Cd, As, Pb, Ni, and Cu exhibit high leaching rates at low pH conditions, with Zn leaching concentrations as high as 2.11 mg/L at pH 2. Zn, Cr, and As exhibit obvious amphoteric leaching characteristics, and the leaching concentration of As at high pH (1.34 mg/L) even exceeds that at low pH (1.31 mg/L). Except for Cu, all heavy metals in CGS exceed the class III groundwater standard in some cases. Therefore, evaluation is needed before resource utilization of CGS due to potential leaching of some heavy metals.

2.
J Environ Manage ; 347: 119107, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37801947

ABSTRACT

Spent selective catalytic reduction (SCR) catalysts are environmentally hazardous and resource-enriching. In this work, V, W, and As in a spent SCR catalyst was extracted by alkali pressure leaching. Results showed that the V, W, and As were loaded on the anatase TiO2 crystal grains as amorphous oxides. The optimum pressure leaching conditions were NaOH concentration of 20 wt%, reaction temperature of 180 °C, reaction time of 120 min, L/S of 10 mL/g, and stirring speed of 300 rpm. The leaching efficiency of W, V, and As reached 98.83%, 100%, and 100%, respectively. The experiment revealed the preferential leaching of V and As rather than W, and the leaching mechanisms of V, W, and As were studied through experiment and density functional theory (DFT). The leaching kinetics of W conformed to a variant of the shrinking core model and the leaching process of W is controlled by both chemical reactions and diffusion processes. During the leaching process, Na2Ti2O4(OH)2 product powder layer was generated, which affects the mass transfer of W. The destruction of the TiO2 skeleton in the spent SCR catalyst is essential for adequate W extraction, especially for the extraction of W embedded in the TiO2 lattice. The DFT simulation result indicated that the V and As loaded onto the TiO2 support are easier to absorb hydroxide ions rather than W, and the leaching reaction energy of V and As was lower than W, As, and V has leaching priority over the leaching of W. Furthermore, an anatase TiO2 photocatalyst with the {001} crystal surface exposed was successfully prepared from the alkali pressure leaching residue. This work provides theoretical support for the metal leaching and utilization of spent SCR catalysts via alkali pressure leaching.


Subject(s)
Alkalies , Titanium , Alkalies/chemistry , Titanium/chemistry , Metals , Oxides/chemistry , Catalysis
3.
Article in English | MEDLINE | ID: mdl-36118093

ABSTRACT

Background: Oxidative stress and memory impairment have been implicated as common functional brain diseases. Nuclear factor E2-related factor 2 (Nrf2) is highly induced in oxidative stress, indicating that Nrf2 is an emerging target of memory therapy. This study aimed to investigate the effect of noni on brain memory impairment induced by hydrocortisone and its protective mechanism in mice. Methods: Male Kunming mice (n = 8/group) were given hydrocortisone by gastric gavage for 14 consecutive days to establish the memory impairment model, except for those in the control group. On the same day, the corresponding drugs were given by gastric gavage. The changes in ethology were examined. The brains were extracted and subjected to western blot analysis and biochemical analyses to assess the activities of antioxidative stress. Results: The middle- and high-dose noni groups exhibited ameliorated ethology, and the high-dose noni group exhibited increased cerebral protein expression of Nrf2, Kelch-like ECH-associated protein 1 (KEAP1), and haem oxygenase-1 (HO-1) compared to the model group. The arrangement of CA3 vertebral cells in the hippocampus of mice was slightly compact, and hyperchromasia and pyknosis were alleviated. Furthermore, biochemical analyses showed that the activities of enzymes related to oxidative stress in the high-dose noni group were increased. Conclusions: Noni might be a powerful antioxidant that can protect nerve cells and may possess potential benefits for the treatment of memory impairment.

4.
Sci Total Environ ; 818: 151856, 2022 Apr 20.
Article in English | MEDLINE | ID: mdl-34822896

ABSTRACT

Coal gasification fine slag (CGFS) is a type of solid waste produced during coal gasification, in which unburned carbon (UC) severely restricts its resource utilization. The removal of UC from CGFS is considered an urgent problem. This study applies PS-1 (a mixture of kerosene and oleic acid at the ratio of 7:3) to improve the flotation separation effect of carbon from CGFS. The flotation adsorption mechanism of PS-1 on UC is revealed by experiment/molecular dynamics simulation and characterization analysis. Results show that long-chain hydrocarbons in PS-1 are adsorbed on the non-polar region of UC by Van der Waals force, while -COOH groups in PS-1 are adsorbed on the polar sites of -COOH and -OH of UC by hydrogen bonds. The synergistic effect of long-chain hydrocarbons and -COOH groups in PS-1 improves the hydrophobicity of the UC surface. Compared with traditional collector kerosene, the combustible recovery rate of foam products can be increased to 68.0%. Collector dosage can be reduced by approximately 50% using PS-1. This study can provide essential guidance for the design of CGS flotation collectors and help realize the comprehensive utilization of coal gasification solid waste.


Subject(s)
Carbon , Coal , Adsorption , Coal/analysis , Coal Ash
5.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3222-3227, 2021 Jul.
Article in Chinese | MEDLINE | ID: mdl-34396740

ABSTRACT

The present study analyzed the current Chinese medicinal health products and Chinese patent medicines effective in boosting memory,aiming at providing references for the formulation and development of memory-boosting health products. The information on memory-boosting health products published by the Department of Special Food Safety Supervision and Management,the State Administration for Market Regulation( SAMR) was collected and the Chinese patent medicines on DRUGDATAEXPY were searched. Microsoft Excel and the TCMISS were used to statistically analyze the characteristics of formulations. A total of 212 memory-boosting health products were obtained from SAMR,including 83 ones containing Chinese medicinal materials. Twelve Chinese herbal medicines showed a usage frequency ≥ 8,with 151 times in use. In DRUGDATAEXPY,258 similar Chinese patent medicines were collected.Twelve Chinese herbal medicines showed a usage frequency ≥ 58,with 907 times in use. Through unsupervised hierarchical entropybased clustering of the above-mentioned Chinese medicinal health products and Chinese patent medicines separately,5 and 12 new formulas were obtained. The selection of Chinese herbal medicines for the new formulas was consistent with the principles of traditional Chinese medicine( TCM) theories,i. e.,tonifying kidney and marrow,benefiting Qi,nourishing Yin,resolving phlegm,and eliminating stasis. According to TCM theories,syndrome differentiation of the users was conducted,and the formulas were designed following the correspondence of syndromes with formulas and Chinese herbal medicines. This study is expected to provide new ideas and methods for the development of Chinese medicinal health products and accurately guide practical applications to exert the advantages of TCM in health care based on syndrome differentiation and improve the effect of Chinese medicinal health products.


Subject(s)
Drugs, Chinese Herbal , Nonprescription Drugs , China , Humans , Medicine, Chinese Traditional , Syndrome
6.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3234-3239, 2021 Jul.
Article in Chinese | MEDLINE | ID: mdl-34396742

ABSTRACT

This study summarized and analyzed the current acne-relieving Chinese medicinal health products and Chinese patent medicines,aiming at providing references for the formulation and development of acne-relieving health products. The information on acne-relieving health products published by the Department of Special Food Safety Supervision and Management,the State Administration for Market Regulation( SAMR) was retrieved,and the Chinese patent medicines on DRUGDATAEXPY were searched. Microsoft Excel and the Traditional Chinese Medicine Inheritance Support System V2. 5( TCMISS) were employed to statistically analyze the characteristics of formulations. Forty-three acne-relieving health products were obtained,including 40 ones containing Chinese herbal medicines. Six Chinese herbal medicines showed a usage frequency ≥8,with 61 times in use totally,including Salviae Miltiorrhizae Radix et Rhizoma( 13),Lonicerae Japonicae Flos( 12),Taraxaci Herba( 11),ALOE( 9),Carthami Flos( 8),and Rhei Radix et Rhizoma( 8). A total of 29 Chinese patent medicines with similar efficacy were collected in DRUGDATAEXPY. Nine Chinese herbal medicines showed a usage frequency ≥6,with 63 times in use,including Rhei Radix et Rhizoma( 10),Glycyrrhizae Radix et Rhizoma( 8),Scutellariae Radix( 8),Lonicerae Japonicae Flos( 7),Angelicae Sinensis Radix( 6),Paeoniae Radix Rubra( 6),Astragali Radix( 6),Paeoniae Radix Alba( 6),and Gardeniae Fructus( 6). Through unsupervised hierarchical entropy-based clustering of the above-mentioned Chinese medicinal health products and Chinese patent medicines,five and three new formulas were obtained,respectively. The selection of Chinese herbal medicines was consistent with the principles of traditional Chinese medicine( TCM) theories in relieving acne,i. e.,dispelling exterior wind,ventilating lungs,clearing heat,dissipating mass,promoting diuresis,relaxing bowels,removing toxin,activating blood,resolving stasis,eliminating phlegm,and regulating Qi. According to the " lung governing skin and body hair" and " interior-exterior relationship between lung and large intestine" in TCM theories,the idea that acne could be treated by relieving constipation was proposed,which provided new methods and references for the research and development of Chinese medicinal health products.


Subject(s)
Acne Vulgaris , Drugs, Chinese Herbal , Acne Vulgaris/drug therapy , China , Glycyrrhiza , Humans , Medicine, Chinese Traditional , Nonprescription Drugs
7.
Sci Total Environ ; 792: 148419, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34147793

ABSTRACT

High-alumina coal fly ash (HAFA) is an important aluminum and silicon resource. In the process of preparing aluminum-silicon materials from HAFA, the influence of impurity elements on its performance must be considered. In this work, the occurrence state of impurities in HAFA, micro morphology, and the bond energy of different impurity coordination were studied. Sulfuric acid leaching method and density functional theory were used to study the leaching behavior of impurities to verify the difficulty of removing different impurity elements. The results show that iron existed in the form of magnetic particles (34.78%), amorphous phase (49.24%), and crystalline phase (15.96%) in HAFA. Titanium mainly existed in amorphous phase (29.34%) and crystalline phase (69.4%). In sulfuric acid leaching, titanium was more difficult to leach, and the content of TiO2 decreased from 2.30% to 2.25%, whereas that of Fe2O3 decreased from 1.50% to 0.86%. The actual leaching behavior of impurity elements was consistent with the simulation results, with more energy required to remove Ti than Fe. These studies of impurity elements in HAFA will provide theoretical support for the preparation of aluminum-silicon materials.


Subject(s)
Coal Ash , Coal , Aluminum , Aluminum Oxide , Titanium
8.
Zhongguo Zhong Yao Za Zhi ; 46(8): 1943-1950, 2021 Apr.
Article in Chinese | MEDLINE | ID: mdl-33982503

ABSTRACT

Based on the research literatures of Passiflora incarnata and the theory of traditional Chinese medicine, the paper discussed the traditional Chinese medicinal properties of P. incarnate, so as to provide a theoretical basis for the compatibility and application of P. incarnata. The literature databases of CNKI, Wanfang, VIP, Web of Science, PubMed and Scopus were selected, and the literatures relating to P. incarnata were reviewed to screen out the scientific research literatures with a high credibility, rational design and reliable conclusions. Foreign pharmacopoeia was consulted, and the listed products were summarized. The traditional Chinese medicine properties of P. incarnata were studied based on 32 clinical trials, 66 pharmacological researches, 64 chemical constituents researches as well as the theory of traditional Chinese medicine. It was preliminarily concluded that the medicinal properties of P. incarnata are sweet, cool, and enter heart, liver channels. The function is mainly to calm the heart and tranquilizing the mind, and calm the liver wind. It is used for hyperactivity of liver-Yang, stagnation of liver-Qi, restlessness of mind, depression, nervousness, insomnia. This paper summarized the source, characteristics of natures, tastes and channel tropism, usage and dosage, function indications of P. incarnata, and defined its clear traditional Chinese medicine property, which lays a theoretical foundation for the compatibility and clinical application of P. incarnata and Chinese medicine.


Subject(s)
Anti-Anxiety Agents , Drugs, Chinese Herbal , Passiflora , Sleep Initiation and Maintenance Disorders , Anxiety , Humans , Medicine, Chinese Traditional , Sleep Initiation and Maintenance Disorders/drug therapy
9.
Zhongguo Zhong Yao Za Zhi ; 46(8): 1960-1966, 2021 Apr.
Article in Chinese | MEDLINE | ID: mdl-33982505

ABSTRACT

Aspalathus linearis is a needle-shaped shrub that grows in the Cedarberg mountains in southern South Africa, with an extremely high medicinal value. In 2014, China has approved A. linearis as a new food material. Through retrieval in CNKI, Wanfang, VIP, Web of Science, PubMed and Scopus databases, the literatures were excluded, classified and summarized.On the basis of Chinese medicine theory, the traditional Chinese medicine properties were deducted. Finally, 264 relevant li-teratures were included and classified into 6 categories: review, planting, chemical composition, clinical study, pharmacological effects and safety. The traditional Chinese medicinal properties were deducted as sweet flavor and neutral property. It enters kidney, spleen, heart and liver channels. The major functions are to tonify the kidney and benefit the essence, nourish Qi and spleen, nourish Yin and prompt the production of body fluid, tranquilize mind, and relieve pain. It can be used for soreness of the waist and fatigue, sexual disinterest, limbs heaviness, thirst due to insufficiency of fluid and internal heat, irritability and insomnia, forget fulness, stomachache, joint pain, dysmenorrhea, headache. Preparation for external use can treat eczema itching. Water decoction(2-15 g) can also be used as tea directly. This paper defined the traditional Chinese medicine properties of A. linearis, so as to provide the theoretical basis for further clinical application.


Subject(s)
Aspalathus , Drugs, Chinese Herbal , China , Female , Medicine, Chinese Traditional
10.
Waste Manag ; 116: 190-195, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32799099

ABSTRACT

High-alumina coal fly ash (HAFA) is an important aluminum and silicon resource. In terms of its comprehensive utilization, how to efficiently separate aluminum and silicon must be resolved. In this work, a mechanochemical activation method in the desilication process is adopted and investigated. Desilication ratio, efficient desilicated ratio, microscopic appearance, and coordination structure change in aluminum-silicon atoms are investigated during mechanochemical activation process. Results indicate that the Al-O-Si coordination structure in HAFA can be transformed from Q4 (3Al) and Q4 (2Al) to reactive Q2 (1Al) structure, and the radio of Q2 (1Al) with high activity increased from 6.93% to 14.47%, which can improve HAFA reaction activity obviously. During the desilication process, the aluminum-silicon mass ratio (A/S) can be elevated from 1.23 to 2.56 after the process optimization, which provides a high-quality raw material for further high-valued utilization of HAFA.


Subject(s)
Coal Ash , Coal , Aluminum , Aluminum Oxide
11.
Zhongguo Zhong Yao Za Zhi ; 45(14): 3481-3488, 2020 Jul.
Article in Chinese | MEDLINE | ID: mdl-32726065

ABSTRACT

In this article, the foreign and domestic literature on alien plant medicine Cynara scolymus was reviewed to explore its properties and functions in traditional Chinese medicine theory, and provide theoretical basis for clinical application and reasonable compatibility. Based on the literature databases of PubMed, Web of Science, Embase, the Cochrane Library, CNKI, VIP and Sinomed, the articles with high reliability related to C. scolymus were screened out and the obtained articles were systematically classified according to clinical application, chemical compositions, pharmacological action, toxic and side effects, etc. In the analysis with traditional Chinese medicine theory, it is concluded that: C. scolymus tastes bitter and slightly cold, attributing to spleen, stomach, liver and gall meridians. It has the functions of eliminating accumulation and guiding stagnation, regulating Qi-flowing for harmonizing stomach, clearing away dampness and heat, resolving turbidity and lowering blood lipids. It can be used for the treatment of dyspepsia, diet reduction, vomiting, nausea, abdominal distention, hypochondriac pain, jaundice, hyperlipidemia, etc. Through the analysis and research of the relevant literature on C. scolymus, the properties and functions of the drug were clarified, which could provide a theoretical basis for further animal experiments and clinical research. The research model of "traditional Chinese medicine theory" for alien plant medicines can provide reference for the introduction and research of botanical drugs around the world, which can greatly enrich Chinese medicine resources and is of great significance for promoting the sustainable development of traditional Chinese medicine.


Subject(s)
Cynara scolymus , Drugs, Chinese Herbal , Meridians , Animals , Medicine, Chinese Traditional , Reproducibility of Results
12.
Dalton Trans ; 47(11): 3864-3871, 2018 Mar 12.
Article in English | MEDLINE | ID: mdl-29450438

ABSTRACT

Li1.6Mn1.6O4 is a representative ion sieve material that is used to recover lithium from salt brines and bitterns owing to its high lithium ion adsorption capacity reaching 11.9-44 mg g-1. However, manganese dissolution during acid treatment hinders the industrial application of the material. For investigating the mechanism of manganese dissolution, the precursor Li1.6Mn1.6O4 and ion sieve H1.6Mn1.6O4 were prepared and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), chemical content analyses, diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS), and X-ray photoelectron spectroscopy (XPS). The results of XRD, SEM, and FT-IR showed that the bulk phase of Li1.6Mn1.6O4 retained the spinel structure, whereas the lattice diminished during acid treatment. The results of chemical content analyses showed that the bulk phase of Li1.6Mn1.6O4 contained a few trivalent manganese atoms and that the mean valence of manganese in the material increased during acid treatment. DRIFTS and XPS exhibited that the surface of Li1.6Mn1.6O4 was mostly full of tetravalent manganese and retained the spinel structure during acid treatment. In the proposed mechanism of manganese dissolution, an electron of trivalent manganese in the bulk phase transfers to the surface and is captured by tetravalent manganese within the acidic environment. Then, tetravalent manganese is converted to bivalent manganese after acquiring sufficient electrons, and dissolution occurs simultaneously.

13.
J Phys Chem A ; 119(45): 11199-207, 2015 Nov 12.
Article in English | MEDLINE | ID: mdl-26485565

ABSTRACT

The present work reports the adsorption mechanisms of aniline and toluene in dry and hydrated montmorillonite (MMT-Na and MMT-Na-W) and tetramethylammonium-cation-modified MMT (MMT-TMA) as determined through density functional theory. These theoretical investigations explicitly demonstrate that cation-π interactions between Na(+)/TMA(+) cations and aromatics play the key role in adsorption of organics over MMT-Na and MMT-TMA. Weak hydrogen bonds between the H atoms of organics and basal O atoms of tetrahedral silicate also stabilize the location of organics. The combination of interactions between water and basal O atoms and between organics and water molecules in hydrated MMT complexes strengthens the adsorption of organics on MMT, resulting in higher formation energies in hydrated organically intercalated MMTs than in the corresponding dry complexes. The adsorption of organics also changes frontier orbital distributions and consequently promotes the preferential occurrence of reactions on the organics rather than on the MMT layers. These adsorption mechanisms predicted by theoretical investigation can be used to explicate the adsorption of aromatic organics on aluminosilicates with different external environment.

14.
Nanoscale ; 5(18): 8375-83, 2013 Sep 21.
Article in English | MEDLINE | ID: mdl-23873181

ABSTRACT

Potassium niobate (KNbO3) microcubes with orthorhombic and tetragonal phases were hydrothermally prepared and characterized by powder X-ray diffraction, nitrogen adsorption-desorption, micro-Raman spectroscopy, Fourier transform infrared spectroscopy, diffuse reflectance UV-visible spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. The photoreactivity of the as-prepared KNbO3 samples was evaluated regarding the hydrogen evolution from aqueous methanol under UV, and the results were compared with that of cubic KNbO3 microcubes. The photocatalytic reactivity was shown to be phase-dependent, following the order cubic > orthorhombic > tetragonal. Insight into the phase-dependent photocatalytic properties was gained by first-principles density functional calculations. The best photocatalytic performance of cubic KNbO3 is ascribed to it having the highest symmetry in the bulk structure and associated unique electronic structure. Further, the surface electronic structure plays a key role leading to the discrepancy in photoreactivity between orthorhombic and tetragonal KNbO3. The results from this study are potentially applicable to a range of perovskite-type mixed metal oxides useful in water splitting as well as other areas of heterogeneous photocatalysis.

15.
J Phys Chem A ; 111(51): 13544-53, 2007 Dec 27.
Article in English | MEDLINE | ID: mdl-18052141

ABSTRACT

The structure and properties of small neutral and cationic CrGen(0,+) clusters, with n from 1 to 5, were investigated using quantum chemical calculations at the CASSCF/CASPT2 and DFT/B3LYP levels. Smaller clusters prefer planar geometries, whereas the lowest-lying electronic states of the neutral CrGe4, CrGe5, and cationic CrGe5+ forms exhibit nonplanar geometries. Most of the clusters considered prefer structures with high-spin ground state and large magnetic moments. Relative to the values obtained for the pure Gen clusters, fragmentation energies of doped CrGen clusters are smaller when n is 3 and 4 and larger when n = 5. The averaged binding energy tends to increase with the increasing number of Ge atoms. For n = 5, the binding energies for Ge5, CrGe5, and CrGe5+ are similar to each other, amounting to approximately 2.5 eV. The Cr atom acts as a general electron donor in neutral CrGen clusters. Electron localization function (ELF) analyses suggest that the chemical bonding in chromium-doped germanium clusters differs from that of their pure or Li-doped counterparts and allow the origin of the inherent high-spin ground state to be understood. The differential DeltaELF picture, obtained in separating both alpha and beta electron components, is consistent with that derived from spin density calculations. For CrGen, n = 2 and 3, a small amount of d-pi back-donation is anticipated within the framework of the proposed bonding model.

16.
J Phys Chem A ; 109(45): 10396-402, 2005 Nov 17.
Article in English | MEDLINE | ID: mdl-16833336

ABSTRACT

Multireference complete active space self-consistent-field CASSCF(10,12)/ANO and second-order perturbation theory MS-CASPT2 calculations were performed to determine the vertical low-lying singlet and triplet states of aniline. The sequence of the seven lower lying triplet states is T1(1(3)A'), T2(1(3)A' '), T3(2(3)A'), T4(3(3)A'), T5(2(3)A' '), T6(4(3)A'), and T7(3(3)A' '). The 3(3)A', 4(3)A', and 3(3)A' ' states are assigned as 3s, 3py, and 3pz Rydberg states, respectively, while other states correspond to pi <-- pi excitations. Both the T1 and T2 states are found to be below at the lowest-lying singlet S1 (1(1)A' ') state. Geometry, vibrational modes, and electron distribution of the lowest lying T1 state were determined using UB3LYP calculations. The vertical and adiabatic singlet-triplet energy gaps DeltaE(S0-T1) amount to 3.7 and 3.5 +/- 0.2 eV, respectively. In clear contrast with the S0 state, the triplet aniline is no longer aromatic, and its protonation occurs preferentially at the ring meta-carbon site, with a proton affinity PA = 243 +/- 3 kcal/mol.


Subject(s)
Aniline Compounds/chemistry , Models, Chemical , Quantum Theory , Molecular Structure
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