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1.
Molecules ; 29(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38893398

RESUMO

Macrocycles composed of diverse aromatic or nonaromatic structures, such as cyclodextrins (CDs), calixarenes (CAs), cucurbiturils (CBs), and pillararenes (PAs), have garnered significant attention due to their inherent advantages of possessing cavity structures, unique functional groups, and facile modification. Due to these distinctive features enabling them to facilitate ion insertion and extraction, form crosslinked porous structures, offer multiple redox-active sites, and engage in host-guest interactions, macrocycles have made huge contributions to electrochemical energy storage and conversion (EES/EEC). Here, we have summarized the recent advancements and challenges in the utilization of CDs, CAs, CBs, and PAs as well as other novel macrocycles applied in EES/EEC devices. The molecular structure, properties, and modification strategies are discussed along with the corresponding energy density, specific capacity, and cycling life properties in detail. Finally, crucial limitations and future research directions pertaining to these macrocycles in electrochemical energy storage and conversion are addressed. It is hoped that this review is able to inspire interest and enthusiasm in researchers to investigate macrocycles and promote their applications in EES/EEC.

2.
Inorg Chem ; 61(44): 17883-17892, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36302095

RESUMO

The strategy to enhance phosphor stability against thermal quenching and moisture conditions will contribute to controlling the feature of phosphor-converted white-light-emitting diodes (pc-WLEDs). Herein, an effective strategy is achieved with the incorporation of Sm3+ ions, and a robust reddish-orange emission (no thermal quenching up to 498 K) is obtained based on Ba3LaNb3O12 as a host. In light of excitation by near-ultraviolet irradiation at 408 nm, Ba3LaNb3O12:Sm3+ gives rise to a typical signal ascribed to the 4G5/2 → 6HJ/2 (J = 5, 7, 9, and 11) transitions of Sm3+ ions. The concentration quenching effect is observed when the Sm3+ content exceeds 10%, and the quenching mechanism is caused by electronic dipole-dipole interactions. Based on the narrow emission curves, a very high color purity (92.4%) could be recorded. The Sm3+ substitution at the Ba2+/La3+ site leads to a rigid structural lattice and abundant electron-trapping centers for the Sm3+ ions, which will be responsible for the zero-thermal-quenching phenomenon. In addition, oleic acid (OA) is selected to form a hydrophobic covering surface structure to protect Ba3LaNb3O12:Sm3+, which can assist in improving the moisture resistance. The most favorable parameters concerning the warm-light emission (a high general color rendering index, Ra, of 85.7 and a low correlated color temperature, CCT, of 4965 K) can be achieved in pc-WLEDs containing an OA-modified sample. Moreover, its luminous efficiency, LE, can maintain 82.9% of its initial value after 120 h under controlled environmental conditions of 85 °C and 85% humidity. These results pave a new way to optimize the sample as a potential candidate for red-emitting materials.

3.
Inorg Chem ; 59(1): 433-442, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31829630

RESUMO

The substitution of metal sites in Mg2TiO4 substrate leads to charge imbalance that will be closely related to a variety of changes including lattice structure, cell distortion, and photophysical properties. Herein, the co-substitution strategy of [Ga3+-Ga3+] for [Mg2+-Ti4+] and Sn4+ for Ti4+ achieves for the first time the novel Mg3Ga2SnO8 (MGS):xMn4+ (x = 0-3%) phosphors with efficient red emissions. In terms of X-ray powder diffraction (XRD) and Rietveld refinement analysis, MGS:Mn4+ possesses a structure isotypic of Mg2TiO4 in the cubic space group Fd3̅m (227). There are two types of octahedra for Mn4+ ions in this structure, where Ga3+ ions completely occupy a group of octahedral sites and Mg2+/Sn4+ has been randomly distributed over another group of octahedral sites. A strong excitation band in the broad spectral range (220-550 nm) has been identified, thus facilitating the commercial uses for blue LED chips excitation. An intense red emission band at 680 nm has been observed due to the characteristic 2Eg-4A2g transition of Mn4+ ions. A concentration quenching effect occurs when the Mn4+ content exceeds 1.5%, and the quenching mechanism is demonstrated to be dipole-quadrupole interactions. Temperature-dependent luminescence measurements support its good thermal stability, and the corresponding activation energy Ea is determined to be 0.2552 eV. The possible luminous mechanism of the Mn4+ ion is explained by the Tanabe-Sugano energy level diagram. The crystal field strength and the Racah parameters together with the nephelauxetic ratio are also determined for Mn4+ in the MGS lattice. High color rendition warm white-light-emitting diodes (WLEDs) based on the optimal phosphor MGS:1.5%Mn4+,1.5%Li+ possess a color rendering index and color temperature of 85.6 and 3658 K, respectively. Its feasibility for application in solid-state white lighting has been verified.

4.
Anal Chem ; 90(7): 4273-4276, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513517

RESUMO

In this work, we develop a sequential self-assembly approach to fabricate interpenetrated binary supramolecular nanofibers consisting of carbazole oligomer 1-cobalt(II) (1-Co2+) coordination nanofibers and oligomer 2 nanofibers for the sensitive detection of six classes of explosives. When exposed to peroxide explosives (e.g., H2O2), Co2+ in 1-Co2+ coordination nanofibers can be reduced to Co+ that can transfer an electron to the excited 2 nanofibers and thereby quench their fluorescence. On the other hand, when exposed to the other five classes of explosives, the excited 2 nanofibers can transfer an electron to explosives to quench their fluorescence. On the basis of the distinct fluorescence quenching mechanisms, six classes of explosives can be sensitively detected. Herein, we provide a new strategy to design broad-band fluorescence sensors for a rich identification of threats.

5.
Anal Chem ; 89(22): 11908-11912, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29086553

RESUMO

In this work, we report a two-member fluorescence array sensor for the effective discrimination of five classes of explosives. This smallest array sensor is composed of tricarbazole-based nanofibers (sensor member 1) and nanoribbons (sensor member 2) deposited as two film bands in a quartz tube. On the basis of a simple comparison of the resulting fluorescence quenching ratios between two sensor members and the response reversibility upon exposure to vaporized explosives, five classes of explosives can be sensitively detected and easily discriminated. This array sensor that has only two sensor members and no complex data analysis represents a new design way for discrimination of a broad class of explosives.

6.
Zhonghua Yi Xue Za Zhi ; 90(28): 1970-3, 2010 Jul 27.
Artigo em Zh | MEDLINE | ID: mdl-20979861

RESUMO

OBJECTIVE: To investigate the role of bacteria in the etiology of chronic prostatitis. METHODS: Complete prostate specimens were obtained at autopsy from 192 organ donors (aged 20 - 38 years old) during 2002 to 2008 who died of non-prostatic diseases. One tissue taken from the peripheral prostatic zone according to McNeal was divided into two pieces. One piece of tissue was taken for routine pathological examinations and immunohistochemical studies of interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α) and IgA. Another one was taken for PCR assay to detect the bacterial 16S rRNA genes (16S rDNA). RESULTS: Of 192 prostate specimens, 64 (33.3%) had pathological changes of chronic prostatitis and 38 (19.8%) specimens was positive for bacterial 16S rDNA. Positive rates of 16S rDNA in chronic prostatitis and non-prostatitis specimens were 50.0% (32/64) and 4.6% (6/128) respectively (χ(2) = 55.185, P < 0.001). Expressions of IL-1ß, TNF-α and IgA in specimens of chronic prostatitis were significantly higher than those in non-prostatitis specimens (P < 0.001). A positive correlation could be found among three immunohistochemical indicators (P < 0.01). In 64 specimens with chronic prostatitis, a significant expression of IL-1ß, TNF-α and IgA was more often demonstrated in 16S rDNA positive group than in 16S rDNA negative group (P < 0.001). CONCLUSIONS: The up-regulations of bacterial 16S rDNA, cytokines and immunoglobulin A are involved in inflammatory response of chronic prostatitis. Bacterial infection may be an important cause of chronic prostatitis.


Assuntos
Imunoglobulina A/metabolismo , Interleucina-1beta/metabolismo , Próstata/metabolismo , RNA Ribossômico 16S/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Bactérias/genética , Genes Bacterianos , Genes de RNAr , Humanos , Masculino , Próstata/microbiologia , Próstata/patologia , Adulto Jovem
7.
Zhonghua Nan Ke Xue ; 16(1): 40-3, 2010 Jan.
Artigo em Zh | MEDLINE | ID: mdl-20180403

RESUMO

OBJECTIVE: To investigate the role of bacteria in the etiology of chronic prostatitis. METHODS: A total of 162 complete prostate specimens were obtained at autopsy from organ donors (aged 20 -38 yr) who died of non-prostatic diseases. Each of the samples from the peripheral zone of the prostate was divided into two parts, one for routine pathological examination and immunohistochemical studies of interleukin (IL)-1beta, tumor necrosis factor-alpha (TNF-alpha) and the nerve growth factor (NGF), and the other for PCR assay to detect the bacterial 16S rRNA gene (16S rDNA). RESULTS: Fifty-one (31.5%) of the total specimens presented pathological changes of chronic prostatitis, of which 44 had mild focal stromal, 5 mild focal stromal and periglandular and 2 mild focal periglandular inflammation. The positive rate of 16S rDNA was 19.1% (31/162), 51.0% (26/51) in the chronic prostatitis and 4.5% (5/111) in the non-prostatitis specimens (chi2 = 29.783, P < 0.01). In the specimens with chronic prostatitis, the expressions of IL-1beta, TNF-alpha and NGF were significantly higher in the 16S rDNA positive than in the 16S rDNA negative group (P < 0.01). CONCLUSION: Bacterial inflammation may play an important role in the etiology of chronic prostatitis.


Assuntos
Próstata/metabolismo , Próstata/microbiologia , Prostatite/metabolismo , Prostatite/microbiologia , Adulto , Doença Crônica , Genes de RNAr , Humanos , Interleucina-1beta/metabolismo , Masculino , Fator de Crescimento Neural/metabolismo , Próstata/patologia , Prostatite/patologia , RNA Bacteriano/genética , RNA Ribossômico , RNA Ribossômico 16S/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
8.
Zhonghua Yi Xue Za Zhi ; 86(14): 976-8, 2006 Apr 11.
Artigo em Zh | MEDLINE | ID: mdl-16759539

RESUMO

OBJECTIVE: To investigate the role of bacteria in chronic prostatitis. METHODS: Complete specimens of prostate were obtained from 140 organ donors, aged 20 - 35, at autopsy. A piece of tissue was collected from the peripheral zone of prostate from each specimen and was divided into 2 parts to undergo pathological examination and PCR so as to detect the 16S ribosomal RNA (16S rRNA) gene of bacteria. RESULTS: Focal mild inflammation was shown in 46 of the 104 specimens (32.9%), including interstitial inflammation in 42 specimens, inflammation in both interstitial and body of gland in 3 specimens, and perigladulitis in 1 specimen. Twenty-seven of the 140 specimens (19.3%) were positive in 16S rRNA gene. The positive rate of 16S rRNA gene of the specimens with prostatitis was 48.9%, significantly higher than that of the specimens without prostatitis (5.3%, P < 0.001). CONCLUSION: Bacteria may play an important role in the pathogenesis of chronic prostatitis.


Assuntos
Próstata/microbiologia , Prostatite/microbiologia , RNA Ribossômico 16S/genética , Adulto , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Humanos , Masculino , Reação em Cadeia da Polimerase
9.
Ai Zheng ; 21(10): 1109-11, 2002 Oct.
Artigo em Zh | MEDLINE | ID: mdl-12508654

RESUMO

BACKGROUND & OBJECTIVE: It is demonstrated that endothelin-1 (ET-1) is synthesized by and released from certain malignant tumor cells, and it plays an important role in growth and development of tumor. This study was designed to investigate the expression of ET-1 in astrocytomas and the relationship between the ET-1 quantity and the grades of astrocytomas. METHOD: ET-1 expression was determined in 70 astrocytoma specimens using Streptavidin-Peroxidase method and image analysis technology. RESULTS: The ET-1 expressed in all of astrocytomas, and the ET-1 expression was mainly located in the cytoplasm. The positive rates of ET-1 in grade IV and III astrocytomas (86.67% and 93.33%) were significantly higher than that in grade II, I and normal astrocytes(75.00%, 66.67%, and 37.50%) (P < 0.05). The results of image analysis on astrocytoma (grade IV, III, II, I and normal control: 0.1875 +/- 0.0227, 0.1516 +/- 0.0134, 0.1215 +/- 0.0116, 0.1048 +/- 0.0143, and 0.0717 +/- 0.0074, respectively) showed that the lower differentiation of astrocytoma, the higher ET-1 expression (P < 0.01). The expression of ET-1 was significantly correleted with the tumor grading (r = 0.863, P < 0.01). CONCLUSION: The ET-1 quantitative analysis may be used as a monitoring index of astrocytoma growing.


Assuntos
Astrocitoma/patologia , Neoplasias do Sistema Nervoso Central/patologia , Endotelina-1/biossíntese , Adolescente , Adulto , Idoso , Astrocitoma/metabolismo , Neoplasias do Sistema Nervoso Central/metabolismo , Endotelina-1/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
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