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1.
Chemphyschem ; : e202400505, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978281

RESUMO

In the catalytic transformation of bio-oil into liquid fuels having alkanes via hydrodeoxygenation (HDO), the acid and metal sites in the catalyst are pivotal for promoting the HDO of lignin-derived phenolic compounds. This study introduces a novel bifunctional catalyst comprising phosphomolybdenum-vanadium heteropolyacids (H4PMo11VO40) coupled with Ni/C. The HDO reaction of the model compound guaiacol was carried out under reaction conditions of 230 °C, revealing the superior performance of H4PMo11VO40 with Ni/C catalysts compared to the conventional acids, even at low dosage. The Keggin structure of H4PMo11VO40 provided a solid catalyst with strong acidic and redox properties, alongside advantages such as ease of synthesis, cost-effectiveness, and tunable acid and redox properties at the molecular level. Characterization of Ni/C and the prepared acid demonstrated favorable pore structure with a mesopore volume of 0.281 cm3/g and an average pore size of 3.404 nm, facilitating uniform distribution and catalytic activity of Ni-metal. Incorporating acid enhances the acidic sites, fostering synergistic interactions between metal and acidic sites within the catalyst, thereby significantly enhancing HDO performance. Guaiacol conversion at 230 °C reached 100%, with a cyclohexane selectivity of 89.3%. This study presents a promising pathway for converting lignin-derived phenolic compounds.

2.
Photochem Photobiol ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943225

RESUMO

Elevated global pollution level is the prime reason that contributes to the onset of various harmful health diseases. The products of Biginelli reaction are enormously used in the pharmaceutical industry as they have antiviral, antibacterial, and calcium channel modulation abilities. This work reports a novel eosin Y sensitized boron graphitic carbon nitride (EY-Ben-g-C3N4) as a photocatalyst that efficiently produced 3,4-dihydropyrimidine-2-(1H)-one by the Biginelli reaction of benzaldehyde, urea, and methyl acetoacetate. The photocatalyst EY-Ben-g-C3N4 showed a successful generation of 3,4-dihydropyrimidine-2-(1H)-one (Biginelli product) in good yield via photocatalysis which is an eco-friendly method and has facile operational process. In addition to the production of Biginelli products, the photocatalyst also showed a remarkable NADH regeneration of 81.18%. The incorporation of g-C3N4 with boron helps increase the surface area and the incorporation of eosin Y which is an inexpensive and non-toxic dye, and in Ben-g-C3N4, enhanced the light-harvesting capacity of the photocatalyst. The production of 3,4-dihydropyrimidine-2-(1H)-one and NADH by the EY-Ben-g-C3N4 photocatalyst is attributed to the requisite band gap, high molar absorbance, low rate of charge recombination, and increased capacity of the photocatalyst to harvest solar light energy.

3.
Chem Asian J ; : e202400217, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752326

RESUMO

With increasing global emphasis on environmental sustainability, the reliance on traditional energy sources such as coal, natural gas, and oil are encountering significant challenges. H2, known for its high energy content and pollution-free usage, emerges as a promising alternative. However, despite the great potential of H2, approximately 95 % of hydrogen production still depends on non-renewable resources. Hence, the shift towards producing H2 from renewable sources, particularly through methods like steam reforming of methanol - a renewable resource - represents a beacon of hope for advancing sustainable energy practices. This review comprehensively examines recent advancements in efficient H2 production using Ni-based catalysts in methanol steam reforming (MSR) and proposes the future prospects. Firstly, the fundamental principles of MSR technology and the significance in clean energy generation are elucidated. Subsequently, the design, synthesis techniques, and optimization strategies for enhancing the catalytic performance of Ni-based catalysts are discussed. Through the analysis of various catalyst compositions, structural adjustments, surface active sites, and modification methods, the review uncovers effective approaches for boosting the activity and durability of MSR reactions. Moreover, the review investigates the causes of deactivation in Ni-based catalysts during MSR reactions and proposes strategies for extending catalyst lifespan through fine design and optimization of operation parameters. Lastly, this review outlines the current research challenges and anticipates the future trends and potential applications of Ni-based catalysts in MSR hydrogen production. By offering a comprehensive critical analysis, this review serves as a valuable reference to enhance MSR hydrogen production efficiency and catalyst performance.

4.
Chem Biodivers ; 21(6): e202400329, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38590163

RESUMO

The need for sunlight chemical renewal and contemporary organic transformation has fostered the advancement of environmentally friendly photocatalytic techniques. For the first time, we report on the novel crafting of a bright future with selenium-infused Eosin-B (Sein-E-B) nanocomposite photocatalysts in this work. The Sein-E-B nanocomposite materials were created using a hydrothermal process for solar chemical regeneration and organic transformation under visible light. The synthesized samples were subjected to UV-DRS-visible spectroscopy, FT-IR, SEM, EDX, EIS and XRD analysis. The energy band gap of the Sein-E-B nanocomposite photocatalyst was measured using UV-DRS, and the result was around 2.06 eV. to investigate the generated Sein-E-B catalytic activity as a nanocomposite for 1,4-NADH/NADPH re-formation and C-N bond activation. This novel photocatalyst offers a promising alternative for the regeneration of solar chemicals and C-N bond creation between pyrrole and aryl halides.


Assuntos
Nanocompostos , Catálise , Estrutura Molecular , Nanocompostos/química , Processos Fotoquímicos , Selênio/química
5.
Gynecol Oncol ; 185: 75-82, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38368816

RESUMO

OBJECTIVE: EGFL6, a growth factor produced by adipocytes, is upregulated in and implicated in the tumorigenesis of multiple tumor types. Given the strong link between obesity and endometrial cancer, we sought to determine the impact of EGFL6 on endometrial cancer. METHODS: EGFL6 expression in endometrial cancer and correlation with patient outcomes was evaluated in the human protein atlas and TCGA. EGFL6 treatment, expression upregulation, and shRNA knockdown were used to evaluate the impact of EGFL6 on the proliferation and migration of 3 endometrial cancer cell lines in vitro. Similarly, the impact of EGFL6 expression and knockdown on tumor growth was evaluated. Western blotting was used to evaluate the impact of EGFL6 on MAPK phosphorylation. RESULTS: EGFL6 is upregulated in endometrial cancer, primarily in cony-number high tumors. High tumor endometrial cancer expression of EGFL6 predicts poor patient prognosis. We find that EGFL6 acts to activate the MAPK pathway increasing cellular proliferation and migration. In xenograft models, EGFL6 overexpression increases endometrial cancer tumor growth while EGFL6 knockdown decreases endometrial cancer tumor growth. CONCLUSIONS: EGFL6 is a marker of poor prognosis endometrial cancers, driving cancer cell proliferation and growth. As such EGFL6 represents a potential therapeutic target in endometrial cancer.


Assuntos
Movimento Celular , Proliferação de Células , Neoplasias do Endométrio , Feminino , Humanos , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Animais , Linhagem Celular Tumoral , Camundongos , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Camundongos Nus , Sistema de Sinalização das MAP Quinases , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Regulação para Cima , Moléculas de Adesão Celular
6.
Chemosphere ; 353: 141491, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395365

RESUMO

Photocatalysis has emerged as a promising approach for generating solar chemical and organic transformations under the solar light spectrum, employing polymer photocatalysts. In this study, our aim is to achieve the regeneration of NADH and fixation of nitroarene compounds, which hold significant importance in various fields such as pharmaceuticals, biology, and chemistry. The development of an in-situ nature-inspired artificial photosynthetic pathway represents a challenging task, as it involves harnessing solar energy for efficient solar chemical production and organic transformation. In this work, we have successfully synthesized a novel artificial photosynthetic polymer, named TFc photocatalyst, through the Friedel-Crafts alkylation reaction between triptycene (T) and a ferrocene motif (Fc). The TFC photocatalyst is a promising material with excellent optical properties, an appropriate band gap, and the ability to facilitate the regeneration of NADH and the fixation of nitroarene compounds through photocatalysis. These characteristics are necessary for several applications, including organic synthesis and environmental remediation. Our research provides a significant step forward in establishing a reliable pathway for the regeneration and fixation of solar chemicals and organic compounds under the solar light spectrum.


Assuntos
NAD , Energia Solar , Fotossíntese , Luz , Luz Solar , Compostos Orgânicos/química
7.
Photochem Photobiol ; 100(1): 41-51, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37458262

RESUMO

Aloe vera-derived graphene (ADG) coupled system photocatalyst, mimicking natural photosynthesis, is one of the most promising ways for converting solar energy into ammonia (NH3 ) and nicotinamide adenine dinucleotide (NADH) that have been widely used to make the numerous chemicals such as fertilizer and fuel. In this study, we report the synthesis of the aloe vera-derived graphene-coupled phenosafranin (ADGCP) acting as a highly efficient photocatalyst for the generation of NH3 and regeneration of NADH from nitrogen (N2 ) and oxidized form of nicotinamide adenine dinucleotide (NAD+ ). The results show a benchmark instance for mimicking natural photosynthesis activity as well as the practical applications for the solar-driven selective formation of NH3 and the regeneration of NADH by using the newly designed photocatalyst.


Assuntos
Aloe , Grafite , Fenazinas , NAD/metabolismo , Amônia , Aloe/metabolismo , Fotossíntese
8.
Photochem Photobiol ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38088069

RESUMO

The photocatalytic oxidation and generation/regeneration of amines to imines and leucodopaminechrome (LDC)/NADH are subjects of intense interest in contemporary research. Imines serve as crucial intermediates for the synthesis of solar fuels, fine chemicals, agricultural chemicals, and pharmaceuticals. While significant progress has been made in developing efficient processes for the oxidation and generation/regeneration of secondary amines, the oxidation of primary amines has received comparatively less attention until recently. This discrepancy can be attributed to the high reactivity of imines generated from primary amines, which are prone to dehydrogenation into nitriles. In this study, we present the synthesis and characterization of a novel polymer-based photocatalyst, denoted as PMMA-DNH, designed for solar light-harvesting applications. PMMA-DNH incorporates the light-harvesting molecule dinitrophenyl hydrazine (DNH) at varying concentrations (5%, 10%, 20%, 30%, and 40%). Leveraging its high molar extinction coefficient and slow charge recombination, the 30% DNH-incorporated PMMA photocatalyst proves to be particularly efficient. This photocatalytic system demonstrates exceptional yields (96.5%) in imine production and high generation/regeneration rates for LDC/NADH (65.27%/78.77%). The research presented herein emphasizes the development and application of a newly engineered polymer-based photocatalyst, which holds significant promise for direct solar-assisted chemical synthesis in diverse commercial applications.

9.
Photochem Photobiol ; 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054563

RESUMO

Sulfur-doped Eosin-B (SDE-B) photocatalysts were synthesized for the first time utilizing sublimed sulfur (S8 ) as a dopant in an in situ thermal copolymerization technique. Sulfur doping not only increased Eosin-B (E-B) absorption range for solar radiation but also improved fixation and oxygenation capabilities. The doped sulfur bridges the S-S bond by substituting for the edge bromine of the E-B bond. The improved photocatalytic activity of SDE-B in the fixation and oxygenation of NAD+ /NADP+ and sulfides using solar light is attributed to the photo-induced hole of SDE-B's high fixation and oxygenation capacity, as well as an efficient suppression of electron and hole recombination. The powerful light-harvesting bridge system created using SDE-B as a photocatalyst works extremely well, resulting in high NADH/NADPH regeneration (79.58/76.36%) and good sulfoxide yields (98.9%) under solar light. This study focuses on the creation and implementation of a sulfur-doped photocatalyst for direct fine chemical regeneration and organic transformation.

10.
Photochem Photobiol ; 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38102890

RESUMO

A solvent-free sulfur-bridge-eosin-Y (SBE-Y) polymeric framework photocatalyst was prepared for the first time through an in situ thermal polymerization route using elemental sulfur (S8 ) as a bridge. The addition of a sulfur bridge to the polymeric framework structure resulted in an allowance of the harvesting range of eosin-Y (E-Y) for solar light. This shows that a wider range of solar light can be used by the bridge material's photocatalytic reactions. In this context, supercharged solar spectrum: enhancing light absorption and hole oxidation with sulfur bridges. This suggests that the excited electrons and holes through solar light can contribute to oxidation-reduction reactions more potently. As a result, the photocatalyst-enzyme attached artificial photosynthesis system developed using SBE-Y as a photocatalyst performs exceptionally well, resulting in high 1,4-NADH regeneration (86.81%), followed by its utilization in the exclusive production of formic acid (210.01 µmol) from CO2 and synthesis of fine chemicals with 99.9% conversion yields. The creation of more effective photocatalytic materials for environmental clean-up and other applications that depend on the solar light-driven absorption spectrum of inorganic and organic molecules could be one of the practical ramifications of this research.

11.
Photochem Photobiol ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37740555

RESUMO

The combination of excellent electronic properties and thermal stability positions orange-derived graphene quantum dots (GQDs) as promising materials for solar light-based applications. Researchers are actively exploring their potential in fields such as photovoltaics, photocatalysis, optoelectronics, and energy storage. Their abundance, cost-effectiveness, and eco-friendly nature further contribute to their growing relevance in cutting-edge scientific research. Furthermore, only GQDs are not much more effective in the UV-visible region, therefore, required band gap engineering in GQDs material. In this context, we designed GQDs-based light harvesting materials, which is active in UV-visible region. Herein we synthesized GQDs coupled with 2,6-diaminoanthrquninone (AQ), that is, GQDs@AQ light harvesting photocatalyst the first time for the oxidation of sulfide to sulfoxide under visible light. For the integrating reactions of sulfide in aerobic conditions under visible light by GQDs@AQ photocatalyst exhibit utmost higher photocatalytic activity than simple GQDs due to low molar extinction coefficient and slow recombination charges. The use of GQDs@AQ light harvesting photocatalyst, showed the excellent organic transformation efficiency of sulfide to sulfoxide with excellent yield (94%). The high efficiency and excellent yield of 94% indicate the effectiveness of GQDs@AQ as a photocatalyst for these specific organic transformations.

12.
Chemosphere ; 341: 139697, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37567274

RESUMO

Indeed, the development of ecologically benign molecular fabrication methods for highly efficient graphene quantum dots-based photocatalysts is of great significant. Graphene quantum dots-based photocatalysts have promising applications in various field, including environmental remediation, energy conversion, and splitting of water. However, ensuring resource reusability and minimizing the environmental impact are crucial considerations in the development. From this perspective, attention has also been paid to the creation of easy to make solar light harvesting graphene quantum dots-based photocatalysts for synthesising pharmaceuticals and functional imines compounds. Imines are excellent significant building blocks in pharmaceutical chemistry and excellent examples of these valuable compounds' synthetic intermediates, and the environmentally friendly oxidative synthesis of imines from amines. Therefore, herein, we designed a facile and efficient condensation route to synthesize the Nen-GQDs@PH photocatalyst. This route involves coupling of 2,4-dinitrophenylhydrazine (PH) with nitrogen-enriched graphene quantum dots (Nen-GQDs). The Nen-GQDs@PH as photocatalyst functions in a highly selective and efficient manner, leading to high amines conversion efficiency to imines (95%). Our results highlight a novel and environmentally safe approach for generating highly selective imines from various types of amines, setting a new benchmark in the current research field.


Assuntos
Grafite , Pontos Quânticos , Grafite/química , Pontos Quânticos/química , Aminas/química , Iminas
13.
Gynecol Oncol ; 171: 49-58, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36804621

RESUMO

OBJECTIVES: Epidermal growth factor EGF-like domain multiple-6 (EGFL6) is highly expressed in high grade serous ovarian cancer and promotes both endothelial cell proliferation/angiogenesis and cancer cell proliferation/metastasis. As such it has been implicated as a therapeutic target. As a secreted factor, EGFL6 is a candidate for antibody therapy. The objectives of this study were to create and validate humanized affinity-matured EGFL6 neutralizing antibodies for clinical development. METHODS: A selected murine EGFL6 antibody was humanized using CDR grafting to create 26 variant humanized antibodies. These were screened and the lead candidate was affinity matured. Seven humanized affinity-matured EGFL6 antibodies were screened for their ability to block EGFL6 activity on cancer cells in vitro, two of which were selected and tested their therapeutic activity in vivo. RESULTS: Humanized affinity matured antibodies demonstrated high affinity for EGFL6 (150 pM to 2.67 nM). We found that several humanized affinity-matured EGFL6 antibodies specifically bound to recombinant, and native human EGFL6. Two lead antibodies were able to inhibit EGFL6-mediated (i) cancer cell migration, (ii) proliferation, and (iii) increase in ERK phosphorylation in cancer cells in vitro. Both lead antibodies restricted growth of an EGFL6 expressing ovarian cancer patient derived xenograft. Analysis of treated human tumor xenografts indicated that anti-EGFL6 therapy suppressed angiogenesis, inhibited tumor cell proliferation, and promoted tumor cell apoptosis. CONCLUSIONS: Our studies confirm the ability of these humanized affinity-matured antibodies to neutralize EGFL6 and acting as a therapeutic to restrict cancer growth. This work supports the development of these antibody for first-in-human clinical trials.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias Ovarianas , Humanos , Animais , Camundongos , Feminino , Linhagem Celular Tumoral , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Proliferação de Células , Proteínas de Ligação ao Cálcio , Moléculas de Adesão Celular
14.
J Bodyw Mov Ther ; 30: 221-225, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35500974

RESUMO

INTRODUCTION: Superior cluneal nerve (SCN) entrapment giving rise to low back pain (LBP) remains undiagnosed many times; in this clinical study authors have evaluated therapeutic role of lidocaine injection of SCN for low back pain relief in patients with SCN entrapment. METHODS: The present study was a prospective, observational study; 25 patients with unilateral LBP over the iliac crest and buttock for more than six months not responding to conservative measures were included in this clinical trial. SCN lidocaine injection was done under fluoroscopy guidance; patients having more than 50% reduction in numeric rating scale (NRS) score, for at least 2 h following SCN injection, were enrolled in the study and followed for 6 months. The primary outcome measure was severity of LBP, measured by NRS score. Secondary outcome measures were percentage pain relief; Oswestry Disability Index (ODI) score, reduction of analgesic usage, DSM-IV score for psychological assessment. All these assessments were done prior to the procedure and at 2 weeks, 1, 3 and 6 months after the procedure. RESULTS: A significant reduction in the NRS scores was observed at 2 weeks, 1, 3 and 6 months after SCN lidocaine injection as compared to the baseline (P value < 0.05); authors also observed a significant pain relief and significantly reduced ODI scores, analgesic consumption and DSM scores compared to the baseline values (P value < 0.05). CONCLUSION: A single SCN lidocaine injection provided significant pain relief in LBP patients with SCN entrapment for a period of 6 months.


Assuntos
Dor Lombar , Bloqueio Nervoso , Síndromes de Compressão Nervosa , Analgésicos , Humanos , Lidocaína/uso terapêutico , Dor Lombar/complicações , Dor Lombar/tratamento farmacológico , Bloqueio Nervoso/métodos , Síndromes de Compressão Nervosa/complicações , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/cirurgia , Estudos Prospectivos
15.
BMJ Case Rep ; 14(9)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531238

RESUMO

Xanthogranulomatous pyelonephritis is a rare condition characterised by destructive granulomatous inflammation of renal parenchyma. Primary renal Aspergillosis has been reported in patients with immunocompromised states such as diabetes, retroviral disease, organ transplant recipients, etc. We present a unique case of an older adult in his early 60s, presenting with fever and left flank pain with renal angle tenderness, diagnosed with primary renal aspergillosis with xanthogranulomatous pyelonephritis. These symptoms resolved with a long duration of antifungal (itraconazole) therapy and nephrectomy. The unique features are the development of fungal pyelonephritis in the absence of any immunocompromising conditions and the development of xanthogranulomatous changes with no risk factors.


Assuntos
Pielonefrite Xantogranulomatosa , Idoso , Aspergillus , Febre , Humanos , Rim , Nefrectomia , Pielonefrite Xantogranulomatosa/diagnóstico por imagem , Pielonefrite Xantogranulomatosa/cirurgia
16.
Ad Hoc Netw ; 111: 102324, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33071687

RESUMO

Unmanned Aerial Vehicles (UAV) have revolutionized the aircraft industry in this decade. UAVs are now capable of carrying out remote sensing, remote monitoring, courier delivery, and a lot more. A lot of research is happening on making UAVs more robust using energy harvesting techniques to have a better battery lifetime, network performance and to secure against attackers. UAV networks are many times used for unmanned missions. There have been many attacks on civilian, military, and industrial targets that were carried out using remotely controlled or automated UAVs. This continued misuse has led to research in preventing unauthorized UAVs from causing damage to life and property. In this paper, we present a literature review of UAVs, UAV attacks, and their prevention using anti-UAV techniques. We first discuss the different types of UAVs, the regulatory laws for UAV activities, their use cases, recreational, and military UAV incidents. After understanding their operation, various techniques for monitoring and preventing UAV attacks are described along with case studies.

17.
Sensors (Basel) ; 21(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375080

RESUMO

The simultaneous influences of the substrate anisotropy and substrate bending are numerically and experimentally investigated in this paper for planar resonators on flexible textile and polymer substrates. The pure bending effect has been examined by the help of well-selected flexible isotropic substrates. The origin of the anisotropy (direction-depended dielectric constant) of the woven textile fabrics has been numerically and then experimentally verified by two authorship methods described in the paper. The effect of the anisotropy has been numerically divided from the effect of bending and for the first time it was shown that both effects have almost comparable but opposite influences on the resonance characteristics of planar resonators. After the selection of several anisotropic textile fabrics, polymers, and flexible reinforced substrates with measured anisotropy, the opposite influence of both effects, anisotropy and bending, has been experimentally demonstrated for rectangular resonators. The separated impacts of the considered effects are numerically investigated for more sophisticated resonance structures-with different types of slots, with defected grounds and in fractal resonators for the first three fractal iterations. The bending effect is stronger for the slotted structures, while the effect of anisotropy predominates in the fractal structures. Finally, useful conclusions are formulated and the needs for future research are discussed considering effects in metamaterial wearable patches and antennas.

18.
Angew Chem Int Ed Engl ; 59(29): 11704-11716, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32017337

RESUMO

Selective and economic conversion of lignocellulosic biomass components to bio-based fuels and chemicals is the major goal of biorefineries, but low yields and selectivity for fuel precursors such as sugars, furanics, and lignin-derived monomers pose significant disadvantages in process economics. In this Minireview we summarize the existing protection strategies used in biomass chemocatalytic conversion processes and focus the discussions on the mechanisms, challenges, and opportunities of each strategy. We introduce a concept of using analogous methods to manipulate biomass catalytic conversion pathways during the upgrading of carbohydrates to fuels and chemicals. This Minireview may provide new insights into the development of selective biorefining processes from a different perspective, expanding the options for selective conversion of biomass to fuels and chemicals.


Assuntos
Biocombustíveis , Biomassa , Carboidratos/química , Catálise , Furanos/química , Lignina/química , Açúcares/química
19.
Angew Chem Int Ed Engl ; 55(5): 1728-32, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26791882

RESUMO

Active sites in carbon-catalyzed phosgene synthesis from gaseous CO and Cl2 have been identified using C60 fullerene as a model catalyst. The carbon atoms distorted from sp(2) coordination in non-planar carbon units are concluded to generate active Cl2 . Experiments and density functional theory calculations indicate the formation of a surface-bound [C60 ⋅⋅⋅Cl2 ] chlorine species with radical character as key intermediate during phosgene formation. It reacts rapidly with physisorbed CO in a two-step Eley-Rideal-type mechanism.

20.
Trop Doct ; 44(3): 156-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24557641

RESUMO

Scrub typhus is re-emerging in India. We describe an outbreak of 45 cases from our tertiary care center in north India. This outbreak included city dwellers who had no history of travel to hilly areas. The classical feature of scrub typhus, the eschar, was also noted rarely in these patients. The changing epidemiology of scrub typhus should be kept in mind while attending patients with acute febrile illness.


Assuntos
Surtos de Doenças , Orientia tsutsugamushi/isolamento & purificação , Tifo por Ácaros/epidemiologia , Adulto , Doenças Transmissíveis Emergentes/epidemiologia , Epidemias , Feminino , Febre , Humanos , Índia/epidemiologia , Masculino , Adulto Jovem
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