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1.
Anal Chem ; 91(17): 11122-11128, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31402644

RESUMO

Accurate quantifications of cellular miRNAs are important not only for accelerating them becoming reliable diagnostics biomarkers but also for deeply understanding their influence on central signaling pathways. Although single-molecule miRNA imaging permits quantifying biomolecules at the single-molecule level, it is limited by the sensitivity and specificity of hybridization-based probes. We report a miRNA single-molecule imaging method by using conjugated polymer nanoparticle (CPN) labeled short DNA probe termed as a nanoflare. The transient hybridization of the nanoflares and target miRNAs yields a featured single-molecule kinetics signal rendering high single-molecule sensitivity and specificity. miRNA can be detected with a remarkable detection limit of 1 fM without using any amplification steps. The discrimination capability of homologous miRNAs was also demonstrated. Taking advantage of the featured single-molecule signal of the nanoflare, we can directly count single miR-21 molecules in single cells by using highly inclined and laminated optical sheet (HILO) microscopy. The statistics of the counting reveals miR-21's cell-to-cell fluctuation and differential expression of tumor cells and normal cells.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31376358

RESUMO

Self-powered photodetection driven by ferroelectric polarization has shown great potential in next-generation optoelectronic devices. Hybrid perovskite ferroelectrics that combine polarization and semiconducting properties have a promising position within this portfolio. Herein, we demonstrate the realization of self-powered photodetection in a new developed biaxial ferroelectric, (EA)2 (MA)2 Pb3 Br10 (1, EA is ethylammonium and MA is methylammonium), which displays high Curie temperature (375 K), superior spontaneous polarization (3.7 µC cm-2 ), and unique semiconducting nature. Strikingly, without an external energy supply, 1 exhibits an direction-selectable photocurrent with fascinating attributes including high photocurrent density (≈4.1 µA cm-2 ), high on/off switching ratio (over 106 ), and ultrafast response time (96/123 µs); such merits are superior to those of the most active ferroelectric oxide BiFeO3 . Further studies reveal that strong inversion symmetry breaking in 1 provides a desirable driving force for carrier separation, accounting for such electrically tunable self-powered photoactive behaviors. This work sheds light on exploring new multifunctional hybrid perovskites and advancing the design of intelligent photoelectric devices.

3.
J Am Chem Soc ; 141(31): 12197-12201, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31339309

RESUMO

Organic-inorganic lead halide hybrids have attracted extensive interest in solid-state lighting, due to their superior color tunability and low-cost solution processing. However, the relatively low photoluminescence quantum efficiency (PLQE) is a common issue for most bulk lead halide hybrids. Inspired by the intriguing luminescence properties of heterometallic complexes, we rationally developed an unprecedented two-dimensional (2D) Pb-Mn heterometallic halide hybrid, (C5H14N2)2Pb4MnCl14 (2), through a precisely tailored synthetic approach based on (C5H14N2)2Pb5Cl14 (1). Intriguingly, 2 features a unique 2D heterometallic halide layer configuration, in which the strong quantum confinement facilitates efficient energy transfer from bound excitons to d-states of Mn2+, resulting in highly sensitized Mn2+emission. The PLQE of 2 is up to 32%, considerably higher than that of pristine 1 (less than 1%). Moreover, 2 presents significant environmental and thermal stability, benefiting from its cluster feature. To our best knowledge, this is the first example of construction of a Pb-Mn heterometallic halide hybrid with bulk highly efficient red emission. This work provides a way to enhance the PLQE of lead halide hybrids via sensitization in rationally designed heterometallic halide hybrids.

4.
Medicine (Baltimore) ; 98(28): e16093, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305392

RESUMO

BACKGROUND: LCZ696 has been introduced in patients with hypertension in several trials. Here, we performed a meta-analysis to evaluate the effect and safety of LCZ696 in hypertensive patients. METHODS: PubMed, Embase, the Cochrane Library and ClinicalTrials.gov databases were searched to identify the available randomized controlled trials (RCTs) investigating the effect and safety of LCZ696 in hypertension patients. The last search date was October 31, 2018. RESULTS: Nine RCTs with 6765 subjects were finally included, in which 8 trials compared the effect and safety between LCZ696 and angiotensin receptor antagonists (ARBs). Evidences showed LCZ696, compared with ARBs, achieved a better blood pressure control rate (OR 1.24, 95% CI: 1.14-1.35), specifically, LCZ696 were better at reducing systolic blood pressure [WMD -4.11 mmHg, 95% CI: (-5.13, -3.08) mmHg], diastolic blood pressure [WMD -1.79 mmHg, 95% CI: (-2.22, -1.37) mmHg], mean 24-hour ambulatory systolic blood pressure [WMD -3.24 mmHg, 95% CI: (-4.48, -1.99) mmHg] and mean 24-hour ambulatory diastolic blood pressure [WMD -1.25 mmHg, 95% CI: (-1.81, -0.69) mmHg]. There was no difference in the events of adverse events (risk ratio [RR] 1.01, 95% CI: 0.39-1.09), serious adverse events (RR 0.80, 95% CI: 0.52-1.22) and discontinuation of treatment for any adverse events (RR 0.79, 95% CI: 0.56-1.11) between LCZ696 group and ARB/placebo group, except LCZ696 reduced the rate of headaches (RR 0.69, 95% CI: 0.48-0.99) while increased cough (RR 2.12, 95% CI: 1.11-4.04; P = .02; I = 25%). CONCLUSION: Our finding provides evidence that LCZ 696 was more effective than ARB on blood pressure control and was safe enough in patients with hypertension.


Assuntos
Aminobutiratos/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Tetrazóis/uso terapêutico , Aminobutiratos/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tetrazóis/efeitos adversos
5.
Artigo em Inglês | MEDLINE | ID: mdl-31321862

RESUMO

In response to ever-increasing application requirements in lighting and displays, a tremendous emphasis is being placed on single-component white-light emission. Single-component inorganic borates doped with rare earth metal ions have shown prominent achievements in white-light emission. The first environmentally friendly defect-induced white-light emitting crystalline inorganic borate, Ba2 [Sn(OH)6 ][B(OH)4 ]2 , has been prepared. Additionally, it is the first borate-stannate without a Sn-O-B linkage. Notably, Ba2 [Sn(OH)6 ][B(OH)4 ]2 shows Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of (0.42, 0.38), an ultrahigh color rendering index (CRI) of 94.1, and an appropriate correlated color temperature (CCT) of 3083 K. Such a promising material will provide a new approach in the development of white-light emitting applications.

7.
Biomed Res Int ; 2019: 1061979, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223610

RESUMO

Background: Doublecortin-like kinase 1 (DCLK1) has been universally identified as a cancer stem cell (CSC) marker and is found to be overexpressed in many types of cancers including breast cancer. However, there is little data regarding the functional role of DCLK1 in breast cancer metastasis. In the present study, we sought to investigate whether and how DCLK1 plays a metastatic-promoting role in human breast cancer cells. Methods: We used Crispr/Cas9 technology to knock out DCLK1 in breast cancer cell line BT474, which basically possesses DCLK1 at a higher level, and stably overexpressed DCLK1 in another breast cancer cell line, T47D, that basically expresses DCLK1 at a lower level. We further analyzed the alterations of metastatic characteristics and the underlying mechanisms in these cells. Results: It was shown that, compared with the corresponding control cells, DCLK1 overexpression led to an increase in metastatic behaviors including enhanced migration and invasion of T47D cells. By contrast, forced depletion of DCLK1 drastically inhibited these metastatic characteristics in BT474 cells. Mechanistically, the epithelial-mesenchymal transition (EMT) program, which is critical for cancer metastasis, was prominently activated in DCLK1-overexpressing cancer cells, evidenced by a decrease in an epithelial marker ZO-1 and an enhancement in several mesenchymal markers including ZEB1 and Vimentin. In addition, DCLK1 overexpression induced the ERK MAPK pathway, which resultantly enhanced the expression of MT1-MMP that is also involved in cancer metastasis. Knockout of DCLK1 could reverse these events, further supporting a metastatic-promoting role for DCLK1. Conclusions: Collectively, our data suggested that DCLK1 overexpression may be responsible for the increased metastatic features in breast cancer cells. Targeting DCLK1 may become a therapeutic option for breast cancer metastasis.

8.
Toxins (Basel) ; 11(6)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195636

RESUMO

Fusarium diseases, including corn root rot, sheath rot, stalk rot, and ear rot are frequently occurring in maize producing areas of China. Fusarium stalk rot and ear rot are the most serious diseases and often occur at the same time, but it is unclear whether there is a correlation between Fusarium composition and disease occurrence. This study was conducted to clarify the relationship between the two diseases. A total of 49 corn stalk rot samples were collected from 15 regions of eight provinces in China from 2016 to 2018. The pathogens were isolated and identified separately from stalks, ear stems, and kernels. The contents of the fumonisins (FB1 and FB2) were detected in kernels. The results showed that the main Fusarium species were found in corn kernels, ear stems and stalks at the same time. The results showed that 1201 strains of Fusarium verticillioides, 668 strains of Fusarium oxysporum, 574 strains of Fusarium graminearum species complex (FGSC), 318 strains of Fusarium equiseti, 95 strains of Fusarium proliferatum, and 40 strains of Fusarium subglutinans were isolated from 1470 corn kernels, 245 ear stems, and 1225 stalks randomly selected from 49 samples. The contamination rate of fumonisins in the 49 samples was 57.1% with an average content of 1.9 µg/g, of which four samples exhibited higher levels as set by the European Commission (4.0 µg/g). These results provide a certain association between stalk rot and ear rot and lay a foundation to study the relationships among Fusarium maize diseases.

9.
Chem Asian J ; 14(13): 2273-2277, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31038830

RESUMO

Organic-inorganic lead halides have recently emerged as promising alternatives to conventional optoelectronic materials, considering their intriguing physical properties. However, organic-inorganic lead halides featuring chirality are seldom explored. Here, a pair of enantiomorphic organic-inorganic hybrid semiconducting lead halides, (R-C5 H14 N2 )PbBr4 (1R) and (S-C5 H14 N2 )PbBr4 (2S), were successfully obtained with the templating of chiral amines. These compounds adopt distinct one-dimensional infinite quantum helices formed by edge-shared transformative lead bromide octahedra. Notably, 1R and 2S present mirror circular dichroism (CD) signals due to the chirality transfer of the enantiopure amines. Furthermore, 1R and 2S exhibit phase-matchable quadratic nonlinear response and typical semiconducting behaviours. This work highlights the potential of lead halides as a new kind of chiral semiconducting materials in spintronic and chiral optical applications.

10.
Water Res ; 159: 375-384, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121405

RESUMO

Dosing ferrous ions (ZVI/Fe2+), combining with oxidants (e.g., H2O2) (ZVI/H2O2), sulfidation treatment (S-ZVI), and introducing a weak magnetic field (ZVI/WMF) have been widely used to enhance the performance of zerovalent iron (ZVI) for reductive removal of contaminants. Taking Se(VI) as a probe contaminant, this study systematically compared the performances of different ZVI systems (i.e., ZVI/Fe2+, ZVI/H2O2, S-ZVI, and ZVI/WMF) for contaminant removal. All the four tested methods could greatly improve the performance of ZVI for Se(VI) removal. Se(VI) was removed by S-ZVI at S/Fe molar ratio of 0.05 with a much greater rate constant than other enhanced-ZVI technologies while the maximum amount of Se(VI) removal was obtained in ZVI/Fe2+ system with Fe2+ applied at 0.5 mM among the four tested enhanced-ZVI technologies at initial pH 6.0. In addition, Se(VI) removal by ZVI/Fe2+ was least influenced by initial pH compared to the other tested enhanced-ZVI systems, implying its good adaptability of pH. The application of these tested methods could significantly increase the electron efficiency from ∼0.5% to 4.06-8.72% and Fe2+ application was much more efficient in enhancing the electron efficiency than the other three methods. Finally, the perspective of these enhanced-ZVI technologies was compared in terms of their reactivity, selectivity, chemical cost, and pH adaptability and some suggestions for their possible application were provided.

11.
J Am Chem Soc ; 141(19): 7693-7697, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31046266

RESUMO

Multiaxial molecular ferroelectrics, in which multiple-directional switching of spontaneous polarization creates diverse properties, have shown many intriguing advantages, making them indispensable complements to conventional inorganic oxides. Despite recent blooming advances, multiaxial molecular ferroelectric with bulk photovoltaic effects still remains a huge blank. Herein, we report a biaxial lead halide ferroelectric, EA4Pb3Br10 (1, EA = ethylammonium), which adopts the unique trilayered perovskite motif with a high Curie temperature of ∼384 K. Particularly, for 1, the distinct symmetry breaking with 4/ mmmF mm2 species leads to the emergence of four equivalent polarization directions in the ferroelectric phase. Based on its biaxial nature, the bulk photovoltaic effect of 1 can be facilely tuned between such multiple directions through electric poling. As far as we know, this is the first report on biaxial hybrid perovskite ferroelectric showing directionally tunable photovoltaic activity. This work provides an avenue to control the bulk physical properties of multiaxial molecular ferroelectrics, and highlights their potential for further applications in the field of smart devices.

12.
Angew Chem Int Ed Engl ; 58(33): 11329-11334, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31115145

RESUMO

A highly efficient Z-scheme photocatalytic system constructed with 1D CdS and 2D CoS2 exhibited high photocatalytic hydrogen-evolution activity of 5.54 mmol h-1 g-1 with an apparent quantum efficiency of 10.2 % at 420 nm. More importantly, its interfacial charge migration pathway was unraveled: The electrons are efficiently transferred from CdS to CoS2 through a transition atomic layer connected by Co-S5.8 coordination, thus resulting in more photogenerated carriers participating in surface reactions. Furthermore, the charge-trapping and charge-transfer processes were investigated by transient absorption spectroscopy, which gave an estimated charge-separation yield of approximately 91.5 % and a charge-separated-state lifetime of approximately (5.2±0.5) ns in CdS/CoS2 . This study elucidates the key role of interfacial atomic layers in heterojunctions and will facilitate the development of more efficient Z-scheme photocatalytic systems.

13.
Ther Apher Dial ; 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31090170

RESUMO

Data remains limited about the optimal nucleos(t)ide analogue therapy for patients infected with hepatitis B virus (HBV) while treated with glucocorticoids because of kidney diseases. We aim to evaluate the safety and efficacy of long-term antiviral therapy with telbivudine (LdT) and entecavir (ETV) in this specific population. In this prospective randomized controlled study, a total of 60 patients with both kidney diseases and chronic hepatitis B were randomly divided into LdT group and ETV group. We analyzed changes in estimated glomerular filtration rate (eGFR), variation in HBV DNA, seroconversion of hepatitis B e antigen (HbeAg) and hepatitis B surface antigen (HBsAg). During the 18 month follow-up period, serum HBV DNA load was decreased significantly at 3, 6, 12, 18 months, compared to the pre-treatment value in both LdT and ETV cohorts. No patients achieved HBeAg loss-seroconversion or HBsAg loss-seroconversion with ETV therapy whilst one patient experienced HBeAg and HBsAg loss-seroconversion with LdT therapy. No significant changes in eGFR were seen in patients with ETV therapy compared to baseline. However, eGFR increased 7.43, 18.97 mL/min/1.73m2 , respectively at 12 and 18 months in LdT group and the changes were significant compared to baseline. Further analysis also demonstrated that eGFR significantly improved 11.8, 23.25 mL/min/1.73m2 at 12 and 18 months in LdT group for patients with impaired renal function. LdT is superior to ETV in patients with chronic hepatitis B and kidney diseases because of the renal protection it confers by increasing eGFR.

14.
Molecules ; 24(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141940

RESUMO

There is growing evidence that neuroinflammation is closely linked to depression. Honokiol, a biologically active substance extracted from Magnolia officinalis, which is widely used in traditional Chinese medicine, has been shown to exert significant anti-inflammatory effects and improve depression-like behavior caused by inflammation. However, the specific mechanism of action of this activity is still unclear. In this study, the lipopolysaccharide (LPS) mouse model was used to study the effect of honokiol on depression-like behavior induced by LPS in mice and its potential mechanism. A single administration of LPS (1 mg/kg, intraperitoneal injection) increased the immobility time in the forced swimming test (FST) and tail suspension test (TST), without affecting autonomous activity. Pretreatment with honokiol (10 mg/kg, oral administration) for 11 consecutive days significantly improved the immobility time of depressed mice in the FST and TST experiments. Moreover, honokiol ameliorated LPS-induced NF-κB activation in the hippocampus and significantly reduced the levels of the pro-inflammatory cytokines; tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and interferon γ (IFN-γ). In addition, honokiol inhibited LPS-induced indoleamine 2,3-dioxygenase (IDO) activation and quinolinic acid (a toxic product) increase and reduced the level of free calcium in brain tissue, thereby inhibiting calcium overload. In summary, our results indicate that the anti-depressant-like effects of honokiol are mediated by its anti-inflammatory effects. Honokiol may inhibit the LPS-induced neuroinflammatory response through the NF-κB signaling pathway, reducing the levels of related pro-inflammatory cytokines, and furthermore, this may affect tryptophan metabolism and increase neuroprotective metabolites.

15.
Scand J Psychol ; 60(3): 203-212, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30900755

RESUMO

Human society has evolved to allow third parties-the court system, parents or other societal arbitrators-to punish norm violators and compensate victims. Few studies explore the effect of stress or time pressure on a third-party judge. Under time pressure, people will likely show a more instinctual reaction or judgment style. We investigated third-party punishment and compensation within the context of unfairly shared losses and gains in a dictator game under time pressure. Our results show that under no time pressure, participants were inclined to punish dictators who unfairly split windfall gains; however, participants chose to compensate victims more than punish the norm-violating dictators in the context of unfairly shared losses. With added time pressure, third-parties were disposed to inflict punishment upon the dictator in both the gain and loss contexts-punishment became the action of choice. Our results shed light on the way observed behavior and stress affect social cognition and decision making in the context of altruistic social interventions and the enforcement of social norms.

16.
Chem Asian J ; 14(9): 1530-1534, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30838780

RESUMO

Inorganic-organic hybrid perovskites, especially two-dimensional (2D) layered halide perovskites, have attracted significant attention due to their unique structures and attractive optoelectronic properties, which open up a great opportunity for next-generation photosensitive devices. Herein, we report a new 2D bilayered inorganic-organic hybrid perovskite, (C6 H13 NH3 )2 (NH2 CHNH2 )Pb2 I7 (HFA, where C6 H13 NH3 + is hexylaminium and NH2 CHNH2 + is formamidinium), which exhibits a remarkable photoresponse under broadband light illumination. Structural characterizations demonstrate that the 2D perovskite structure of HFA is constructed by alternant stacking of inorganic lead iodide bilayered sheets and organic hexylaminium layers. Optical absorbance measurements combined with density functional theory (DFT) calculations suggest that HFA is a direct band gap semiconductor with a narrow band gap (Eg ) of ≈2.02 eV. Based on these findings, photodetectors based on HFA crystal wafer are fabricated, which exhibit fascinating optoelectronic properties including large on/off current ratios (over 103 ), fast response speeds (τrise =310 µs and τdecay =520 µs) and high responsivity (≈0.95 mA W-1 ). This work will contribute to the design and development of new two-dimensional bilayer inorganic-organic hybrid perovskites for high-performance photosensitive devices.

17.
J Am Chem Soc ; 141(9): 3812-3816, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30775915

RESUMO

Antiferroelectric materials have been regarded as a promising candidate for electronic energy storage devices, due to their natural double polarization versus electric field ( P- E) hysteresis loops. Currently, two-dimensional organic-inorganic hybrid perovskites with structural diversity and tunability, have received blooming interests, whereas above-room-temperature antiferroelectrics are still unreported in this perovskite system. Herein, for the first time, we successfully acquire a two-dimensional Ruddlesden-Popper hybrid perovskite antiferroelectric, ((CH3)2CHCH2NH3)2CsPb2Br7 (1), which shows an above-room-temperature Curie temperature at 353 K, trigging by the synergistic dynamic motion of inorganic Cs atoms and organic isobutylammonium cations. Intriguingly, the antiferroelectricity of 1 existing over a wide temperature range of 298-353 K are revealed by the distinct double P- E hysteresis loops. Besides, 1 possesses remarkable energy storage efficiency up to 69%, comparable to those of some reported inorganic antiferroelectric ceramics, promoting 1 potential application in energy storage devices. This work provides an avenue to construct novel antiferroelectric materials for high-performance electronic device applications.

18.
J Am Chem Soc ; 141(9): 3833-3837, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30791686

RESUMO

The non-π-conjugated sulfate system has long been overlooked as potential deep-UV nonlinear optical (NLO) materials. Here we report two asymmetric anhydrous sulfates, namely, NH4NaLi2(SO4)2 (Ι) and (NH4)2Na3Li9(SO4)7 (Π), which consist of non-π-conjugated [SO4]2- anions. Their single crystals can be readily grown by a facile evaporation method from water solution. Both sulfates are transparent down to the deep-UV region. Interestingly, there is a large NLO gap between I and Π, with phase-matching NLO responses of 1.1 and 0.5 times that of the benchmark KH2PO4, respectively. The first-principles studies reveal that the non-π-conjugated [SO4]2- anions are the dominate NLO-active groups, and the large NLO gap between I and Π can be ascribed to the nonbonding O 2 p orbitals of different orientations in the crystallographically independent S1O4 groups. This work provides an innovative non-π-conjugated source that is distinct from the traditional π-conjugated ones for deep-UV NLO materials.

19.
ACS Appl Mater Interfaces ; 11(11): 10452-10461, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30801182

RESUMO

Iron deficiency anemia (IDA) is a common nutritional disease suffered by 1 billion people. To develop a new drug which avoids the side effects of traditional oral iron supplementation for IDA treatment, we have designed Fe3O4@ Astragalus polysaccharide core-shell nanoparticles (Fe3O4@APS NPs) and demonstrated them to be an efficient therapeutic drug for IDA treatment in vivo. The Fe3O4@APS NPs have been successfully synthesized with good water solubility and stability, especially in imitated digestion. Cytotoxicity assessment in cells and pathological tests in mice justify their good biocompatibility and low toxicity. The IDA treatment in rats shows that they have efficient therapeutic effect, which is contributed to both the iron element supplement from Fe3O4 and the APS-stimulated hematopoietic cell generation. Moreover, the superparamagnetic Fe3O4@APS NPs are capable for use as a magnetic resonance imaging contrast agent. This study presents the possibility of nanocomposites involving purified natural products from Chinese herb medicine for biomedical applications.


Assuntos
Anemia Ferropriva/terapia , Óxido Ferroso-Férrico/química , Polissacarídeos/química , Anemia Ferropriva/patologia , Anemia Ferropriva/veterinária , Animais , Astrágalo (Planta)/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Estabilidade de Medicamentos , Humanos , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imagem por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/toxicidade , Ratos , Ratos Wistar , Solubilidade
20.
Inorg Chem ; 58(3): 1733-1737, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30652880

RESUMO

An asymmetric structure is the necessary requirement for second-order nonlinear-optical (NLO) materials, which have important applications in modern science and technology. Here we report two isostructural asymmetric compounds, RbBPO4F and CsBPO4F. Both compounds crystallize in cubic space group P213 (No. 198) with three-dimensional (3D) gismondine-like structures. Remarkably, in spite of the same basic structural units BO3F and PO4, both structures are distinct from the previously reported derivative KBPO4F, which crystallizes in a monoclinic space group Cc (No. 9) with a two-dimensional (2D)-layered structure. Careful structural analysis reveals that this structural transformation (from a monoclinic 2D structure to cubic 3D structures) should be aroused by the different alkaline ionic radii. To the best of our knowledge, such an abrupt structural transformation by alkaline elements is reported in all-inorganic asymmetric compounds for the first time. The structural transformation from 2D to 3D structures is favorable to eliminate the layered growth habit. This study will shed deep insight in the structural modulation of asymmetric compounds.

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