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1.
Angew Chem Int Ed Engl ; 63(20): e202402910, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38441480

RESUMO

The challenge of constructing a mechanically robust yet lightweight artificial solid-electrolyte interphase layer on lithium (Li) anodes highlights a trade-off between high battery safety and high energy density. Inspired by the intricate microstructure of the white sea urchin, we first develop a polyvinyl fluoride-hexafluoropropylene (PVDF-HFP) interfacial layer with a triple periodic minimal surface structure (TPMS) that could offer maximal modulus with minimal weight. This design endows high mechanical strength to an ordered porous structure, effectively reduces local current density, polarization, and internal resistance, and stabilizes the anode interface. At a low N/P ratio of ~3, using LiFePO4 as the cathode, Li anodes protected by TPMS-structured PVDF-HFP achieve an extremely low capacity-fading-rate of approximately 0.002 % per cycle over 200 cycles at 1 C, with an average discharge capacity of 142 mAh g-1. Meanwhile, the TPMS porous structure saves 50 wt % of the interfacial layer mass, thereby enhancing the energy density of the battery. The TPMS structure is conducive to large-scale additive manufacturing, which will provide a reference for the future development of lightweight, high-energy-density secondary batteries.

2.
J Phys Chem Lett ; 15(11): 3103-3108, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38470075

RESUMO

Polymer-lined autoclaves are commonly believed to be highly durable and inert in hydrothermal reactions. Herein, we use the hydrothermal synthesis of AlPO-18 zeolite as a case study to demonstrate that the choice of autoclave materials (polytetrafluoroethylene or para-polyphenylene) does significantly affect the product of zeolite synthesis. A small amount of glass fiber in the PPL-lined autoclave unexpectedly functions as a source of silicon and yields SAPO-34 instead of AlPO-18 as the product. The outcomes of 19 successive experiments conducted with a single PPL-lined autoclave exhibit significant variations, further highlighting that the impurities arising from the autoclaves should be considered during the hydrothermal synthesis procedure. In contrast to SAPO-34 synthesized by the conventional method, which displays only Si(4Al) at a low Si/Al ratio, SAPO-34 synthesized in the PPL-lined autoclave exhibits multiple silicon coordination environments. This outcome provides new physical insights into the silicon incorporation mechanism and proposes a viable strategy for regulating the silicon coordination environment at low Si/Al ratios.

3.
Molecules ; 28(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836792

RESUMO

Fabricating heterostructures with abundant interfaces and delicate nanoarchitectures is an attractive approach for optimizing photocatalysts. Herein, we report the facile synthesis of BiOCl nanoflake/FeOCl nanospindle heterostructures through a solution chemistry method at room temperature. Characterizations, including XRD, SEM, TEM, EDS, and XPS, were employed to investigate the synthesized materials. The results demonstrate that the in situ reaction between the Bi precursors and the surface Cl- of FeOCl enabled the bounded nucleation and growth of BiOCl on the surface of FeOCl nanospindles. Stable interfacial structures were established between BiOCl nanoflakes and FeOCl nanospindles using Cl- as the bridge. Regulating the Bi-to-Fe ratios allowed for the optimization of the BiOCl/FeOCl interface, thereby facilitating the separation of photogenerated carriers and accelerating the photocatalytic degradation of RhB. The BiOCl/FeOCl heterostructures with an optimal composition of 15% BiOCl exhibited ~90 times higher visible-light photocatalytic activity than FeOCl. Based on an analysis of the band structures and reactive oxygen species, we propose an S-scheme mechanism to elucidate the significantly enhanced photocatalytic performance observed in the BiOCl/FeOCl heterostructures.

4.
Nano Lett ; 23(16): 7260-7266, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37534944

RESUMO

Understanding the oxidation mechanism of metal nanoparticles under ambient pressure is extremely important to make the best use of them in a variety of applications. Through ambient pressure transmission electron microscopy, we in situ investigated the dynamic oxidation processes of Ni nanoparticles at different temperatures under atmospheric pressure, and a temperature-dependent oxidation behavior was revealed. At a relatively low temperature (e.g., 600 °C), the oxidation of Ni nanoparticles underwent a classic Kirkendall process, accompanied by the formation of oxide shells. In contrast, at a higher temperature (e.g., 800 °C), the oxidation began with a single crystal nucleus at the metal surface and then proceeded along the metal/oxide interface without voids formed during the whole process. Through our experiments and density functional theory calculations, a temperature-dependent oxidation mechanism based on Ni nanoparticles was proposed, which was derived from the discrepancy of gas adsorption and diffusion rates under different temperatures.

5.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903580

RESUMO

The rational regulation of catalyst active sites at atomic scale is a key approach to unveil the relationship between structure and catalytic performance. Herein, we reported a strategy for the controllable deposition of Bi on Pd nanocubes (Pd NCs) in the priority order from corners to edges and then to facets (Pd NCs@Bi). The spherical aberration-corrected scanning transmission electron microscopy (ac-STEM) results indicated that Bi2O3 with an amorphous structure covers the specific sites of Pd NCs. When only the corners and edges of the Pd NCs were covered, the supported Pd NCs@Bi catalyst exhibited an optimal trade-off between high conversion and selectivity in the hydrogenation of acetylene to ethylene under ethylene-rich conditions (99.7% C2H2 conversion and 94.3% C2H4 selectivity at 170 °C) with remarkable long-term stability. According to the H2-TPR and C2H4-TPD measurements, the moderate hydrogen dissociation and the weak ethylene adsorption are responsible for this excellent catalytic performance. Following these results, the selectively Bi-deposited Pd nanoparticle catalysts showed incredible acetylene hydrogenation performance, which provides a feasible perspective to design and develop highly selective hydrogenation catalysts for industrial applications.

6.
Chem Commun (Camb) ; 59(15): 2157-2160, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36727587

RESUMO

Ink jet printing is for the first time introduced into the synthesis of aluminophosphate (AlPO) and silicoaluminophosphate (SAPO) zeolite. As a high-throughput technique, 256 zeolite precursors with multiple formulations could be obtained within 2 h, while the product phase was regulated relative to the variant compositions.

7.
Molecules ; 27(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36296557

RESUMO

The direct hydroxylation of benzene is a green and economical-efficient alternative to the existing cumene process for phenol production. However, the undesired phenol selectivity at high benzene conversion hinders its wide application. Here, we develop a one-pot synthesis of protonated g-C3N4 supporting vanadia catalysts (V-pg-C3N4) for the efficient and selective hydroxylation of benzene. Characterizations suggest that protonating g-C3N4 in diluted HCl can boost the generation of amino groups (NH/NH2) without changing the bulk structure. The content of surface amino groups, which determines the dispersion of vanadia, can be easily regulated by the amount of HCl added in the preparation. Increasing the content of surface amino groups benefits the dispersion of vanadia, which eventually leads to improved H2O2 activation and benzene hydroxylation. The optimal catalyst, V-pg-C3N4-0.46, achieves 60% benzene conversion and 99.7% phenol selectivity at 60 oC with H2O2 as the oxidant.


Assuntos
Benzeno , Fenol , Hidroxilação , Fenol/química , Benzeno/química , Peróxido de Hidrogênio , Fenóis/química , Oxidantes
8.
9.
Inorg Chem ; 60(21): 16658-16665, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34672543

RESUMO

Core-shell structured nanomaterials with delicate architectures have attracted considerable attention for realizing multifunctional responses and harnessing multiple interfaces for enhanced functionalities. Here, we report a controllable synthesis of core-shell structured Mn3O4@SiO2NB nanomaterials consisting of Mn3O4 nanorods covered with a shell of SiO2 nanobubbles. A series of Mn3O4@SiO2NB catalysts with tunable secondary structures can be synthesized by simply tuning the feeding ratio and the modification conditions. The as-synthesized Mn3O4@SiO2NB catalysts exhibit excellent catalytic performance in the degradation of methylene blue (MB) because the Fenton-type reaction between Mn3O4 and H2O2 is confined in an MB-rich environment created by the SiO2 nanobubble shell. The confined Fenton-type catalysis maximizes the contact of MB molecules with the reactive oxygen species and significantly promotes the degradation efficiency of MB. Under optimal conditions, Mn3O4@SiO2NB-0.4 can reach a degradation efficiency of 92% at room temperature and neutral pH within 12 min, which outperforms most reported Mn-based catalysts.

10.
Nat Commun ; 12(1): 5770, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599160

RESUMO

Metal/oxide interface is of fundamental significance to heterogeneous catalysis because the seemingly "inert" oxide support can modulate the morphology, atomic and electronic structures of the metal catalyst through the interface. The interfacial effects are well studied over a bulk oxide support but remain elusive for nanometer-sized systems like clusters, arising from the challenges associated with chemical synthesis and structural elucidation of such hybrid clusters. We hereby demonstrate the essential catalytic roles of a nanometer metal/oxide interface constructed by a hybrid Pd/Bi2O3 cluster ensemble, which is fabricated by a facile stepwise photochemical method. The Pd/Bi2O3 cluster, of which the hybrid structure is elucidated by combined electron microscopy and microanalysis, features a small Pd-Pd coordination number and more importantly a Pd-Bi spatial correlation ascribed to the heterografting between Pd and Bi terminated Bi2O3 clusters. The intra-cluster electron transfer towards Pd across the as-formed nanometer metal/oxide interface significantly weakens the ethylene adsorption without compromising the hydrogen activation. As a result, a 91% selectivity of ethylene and 90% conversion of acetylene can be achieved in a front-end hydrogenation process with a temperature as low as 44 °C.

11.
Angew Chem Int Ed Engl ; 60(26): 14571-14577, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33826203

RESUMO

The development of materials integrated with ultrasmall multi-metal nanoparticles (UMMNs) and mesoporous zeolite is a considerable challenge in chemistry and materials science. We designed a trifunctional surfactant, in which the pyridyl benzimidazole in the hydrophobic tail generates the mesopores through π-π stacking; the diquaternary ammonium in the hydrophilic headgroup direct the formation of MFI zeolite sheets and the nitrogen atoms in the heterocyclic rings coordinate with various metal ions to form UMMNs confined in the zeolite matrix after calcination and reduction. A library of 56 UMMNs confined within both micropores and mesopores of MFI zeolites (MMZs) with 4 mono-, 14 bi- and 38 tri-metallic nanoparticles (sizes of 1.3-4.7 nm) of combinations of Rh, Pd, Pt, Au, Fe, Co, Ni, Cu and Zn were made. An improved catalytic performance was exhibited in the sequence of Rh-MMZ

12.
Nanoscale ; 13(6): 3709-3722, 2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33544114

RESUMO

Rational synthesis of bi- or multi-metallic nanomaterials with both dendritic and porous features is appealing yet challenging. Herein, with the cubic Cu2O nanoparticles composed of ultrafine Cu2O nanocrystals as a self-template, a series of Pd-Cu nanocrystals with different morphologies (e.g., aggregates, porous nanodendrites, meshy nanochains and porous nanoboxes) are synthesized through simply regulating the molar ratio of the Pd precursor to the cubic Cu2O, indicating that the galvanic replacement and Kirkendall effect across the alloying process are well controlled. Among the as-developed various Pd-Cu nanocrystals, the porous nanodendrites with both dendritic and hollow features show superior electrocatalytic activity toward formic acid oxidation. Comprehensive characterizations including three-dimensional simulated reconstruction of a single particle and high-resolution transmission electron microscopy reveal that the surface steps, defects, three-dimensional architecture, and the electronic/strain effects between Cu and Pd are responsible for the outstanding catalytic activity and excellent stability of the Pd-Cu porous nanodendrites.

13.
Front Pharmacol ; 12: 819482, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111069

RESUMO

Background: RYR is a commonly used lipid-lowering dietary supplements in Asian and European countries, showing considerable benefits and low toxicity. This quantitative study aims to present high-quality evidence regarding the efficacy and safety of RYR in treating hyperlipidemia, in order to promote its clinical application. Methods: PubMed, embase, and Cochrane Central Register of Controlled Trials databases were systematically searched, and high-quality randomized controlled trials comparing RYR with non-RYR interventions were included. RevMan5.3 software was used to conduct the meta-analysis. Results: A total of 1,012 individuals participated in this study (481 in the experimental and 531 in the control group). In comparison to statins, RYR was more effective in lowering TG (MD, -19.90; 95% CI, -32.22 to -7.58; p = 0.002), comparable in lowering LDL-C and elevating HDL-C, and less effective in lowering TC (MD, 12.24; 95% CI, 2.19 to 22.29; p = 0.02). Compared with nutraceutical, RYR significantly reduced TC (MD, -17.80; 95% CI, -27.12 to -8.48; p = 0.0002) and LDL-C (MD, -14.40; 95% CI, -22.71 to -6.09; p = 0.0007), and elevated HDL-C (MD, 7.60; 95% CI, 4.33 to 10.87; p < 0.00001). Moreover, RYR effectively synergized nutraceutical to further reduce TC (MD, -31.10; 95% CI, -38.83 to -23.36; p < 0.00001), LDL-C (MD, -27.91; 95% CI, -36.58 to -19.24; p < 0.00001), and TG (MD, -26.32; 95% CI, -34.05 to -18.59; p < 0.00001). Additionally, RYR significantly reduced apoB (MD, -27.98; 95% CI, -35.51 to -20.45; p < 0.00001) and, whether alone or in combination, did not increase the risk of adverse events in patients with hyperlipidemia. Conclusion: RYR at 200-4800 mg daily appears to be a safe and effective treatment for hyperlipidemia, effectively regulating blood lipid levels with an exceptional impact on TG. Looking forward, high-quality clinical trials with longer observation periods are required to evaluate the efficacy and safety of RYR as a long-term medication. Systematic Review Registration: (https://www.crd.york.ac.uk/PROSPERO/), identifier (CRD4202128450).

14.
Front Chem ; 8: 252, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318548

RESUMO

Selective oxidation of methane to methanol has been often considered as a "holy grail" reaction in catalysis. Herein, we systematically investigate the effect of solution pH and Pd-to-Au ratio of AuPd x colloid on the catalytic performance of methane oxidation. It is revealed that these two parameters can determine the amount of H2O2 participated in the reaction, which is linearly related to the productivity of oxygenates. A high catalytic performance in methane activation requires a high utilization of H2O2 to generate more ·OH. The optimal pH is 3.0 and the optimal Pd-to-Au ratio is between 0.1 to 0.7.

15.
Sci Rep ; 10(1): 4719, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170205

RESUMO

It is challenging to develop a low-cost household water treatment (HWT) that simultaneously deliver an effective and robust way for safe and reliable water supply. Here, we report a simple flow-through filter made by zeolite-cotton packing in a tube (ZCT) as low-cost HWT device to remove heavy metal ions from contaminated water. The zeolite-cotton is fabricated by an on-site template-free growth route that tightly binds mesoporous single-crystal chabazite zeolite onto the surface of cotton fibers. As a result, the ZCT set-up with optimized diameter achieves both high adsorption efficiency, proper flow rate, reliable supply and strong stability at the same time. After flowed through the set up packed with 10 g of zeolite-cotton, 65 mL 1000 ppm Cu2+ solution was purified down to its safety limit (<1 ppm). Notably, their efficiency remains unaltered when filtering several ions simultaneously. In a simulated purification process, 8 L of water contaminated by Cu2+, Cd2+ and Pb2+ could be transformed into drinking water and it enables the removal of heavy metals to concentrations of below 5 ppb (µg L-1). We also show that the ZCT can be used for disinfection by introducing Ag-exchanged zeolite-cotton without contaminating the water with Ag ions (<0.05 ppm).

16.
Expert Rev Gastroenterol Hepatol ; 14(1): 55-64, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31062631

RESUMO

Objectives: To improve the prognostic accuracy of 8th edition of American Joint Committee on Cancer TNM staging system for gastric cancer by reclassifying N3a category.Methods: 1446 patients who underwent R0 surgery for histologically proven gastric cancers with ≥16 lymph nodes retrieved were selected.Results: Significant prognostic difference was observed among patients in N3a category ('7-10' group vs '11-15' group; P = 0.029). We proposed a revised pN category in which patients with '7-10' metastatic lymph nodes were categorized as r-N3a, '11-15' as r-N3b, and '>15' as r-N3c. Prognosis for patients in T2r-N3aM0 was similar to that of patients in T4aN0M0/T3N1M0/T2N2M0/T1r-N3bM0 (P = 0.584), but significantly better than that of patients in T4bN0M0/T4aN1-2M0/T3N2M0/T2r-N3bM0 (P = 0.031). Similarly, prognoses for patients in T3r-N3aM0 and T4ar-N3aM0 were similar to that of patients in T4bN0M0/T4aN1-2M0/T3N2M0/T2r-N3bM0 (P = 0.136; P = 0.193), but significantly better than that of patients in T4bN1-2M0/T4ar-N3bM0/T3r-N3bM0/T1-2r-N3cM0 (P = 0.011; P = 0.017). A revised TNM system was also proposed, in which T2r-N3aM0 was incorporated into stage IIB, T3r-N3aM0 and T4ar-N3aM0 into stage IIIA. The revised TNM system had better homogeneity, discriminatory ability, and monotonicity of gradients than the 8th edition system.Conclusion: Patients with 7-10 metastatic lymph nodes in T2-T4a categories should be considered lower stage in the final TNM stage.


Assuntos
Linfonodos/patologia , Estadiamento de Neoplasias/métodos , Neoplasias Gástricas/classificação , Neoplasias Gástricas/patologia , China , Gastrectomia/métodos , Humanos , Excisão de Linfonodo/métodos , Metástase Linfática , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia
17.
Inorg Chem ; 58(13): 8525-8532, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31185539

RESUMO

Heterostructural engineering and three-dimensional architecture construction are effective strategies to optimize the photocatalytic performance of semiconductors. Herein, we integrate these two strategies and controllably synthesize ZnO-BiOI heterostructures with well-defined architectures. Microstructural and surface analysis reveals that the strong electronic interaction between ZnO and Bi3+ ensures a bounded nucleation and growth of BiOI on the surface of ZnO, which leads to the formation of ZnO-BiOI nanorod heterostructures (ZnO-BiOI-NR) with very high dispersion of BiOI on ZnO nanorods. In contrast, when the nucleation and growth of BiOI occurs before reacting with ZnO nanorods, ZnO-BiOI heterostructures (ZnO-BiOI-NF) are composed of BiOI nanoflowers (NFs) and ZnO nanorods. The precise control over the interfaces of ZnO-BiOI heterostructures provides ideal models to investigate the influence of the interfaces on the catalytic performance of heterostructures. It is important to highlight that the photocatalytic activity of ZnO-BiOI-NR is 12 times higher than that of ZnO-BiOI-NF. Mechanism studies suggest that the abundant ZnO-BiOI interfaces in ZnO-BiOI-NR benefit the generation and separation of hole-electron pairs, which consequently improve the catalytic performance.

18.
J Clin Pathol ; 72(2): 165-171, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30467239

RESUMO

AIMS: The prognostic significance of infiltration growth pattern (INF) in patients with gastric cancer (GC) remains controversial. In the present study, we evaluated the impact of INF pattern on the prognosis of patients with advanced GC. METHODS: A total of 1455 patients with advanced GC who underwent curative gastrectomy in our institution were retrospectively analysed. All patients were histopathologically classified as INFa/b and INFc pattern according to the Japanese Classification of Gastric Cancer. The prognostic difference between two patterns was compared and clinicopathological features were analysed. RESULTS: The prognosis of the patients with INFc pattern was poorer than that of those with INFa/b pattern (5-year disease-free survival, INFa/b: 48.4% vs INFc: 33.5%, p < 0.001), even when they were stratified according to lymph node metastasis and the tumour, node, metastases stage. In addition, the subgroup analysis indicated that INFc pattern was significantly associated with poorer prognosis of T2-T3 stage patients (T2, INFa/b: 72.7% vs INFc: 55.4%; T3, INFa/b: 47.4% vs INFc: 33.5%; p<0.001). However, a similar result was not observed among T4a stage patients (INFa/b: 26.8% vs INFc: 24.8%, p>0.05). The prognosis of T2 stage patients with INFc pattern was similar to that of T3 stage patients with INFa/b pattern (p>0.05). Also, there was no significantly prognostic difference between T3 stage patients with INFc pattern and T4a stage patients (p>0.05). The multivariate analysis indicated that INF pattern was an independent prognostic factor for patients with advanced GC (HR 1.259, 95%CI 1.089 to 1.454). CONCLUSION: In view of its prognostic significance, histopathological evaluation of INF pattern in surgically resected specimens should be recommended in patients with advanced GC.


Assuntos
Adenocarcinoma/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Adulto Jovem
19.
Nutr Cancer ; 70(8): 1254-1263, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30686045

RESUMO

OBJECTIVE: In this study, we performed a systematic review and meta-analysis to evaluate the impact of preoperative underweight status on postoperative complications and survival outcome of gastric cancer (GC) patients. METHODS: The related studies were identified by searching PubMed and Embase databases. According to the body mass index (BMI), all patients were classified into underweight group (<18.5 kg/m2) and normal weight group (≥18.5 kg/m2, <25 kg/m2). The relevant data were extracted and pooled effect size were assessed using a fixed effect model or random effect model. RESULTS: A total of 12 studies were included in this meta-analysis. The results indicated that underweight patients had a higher risk of postoperative complications than normal weight patients (RR: 1.28, 95% CI: 1.01-1.61, P < 0.05; I2 = 57.3%), especially for pulmonary infection (RR: 1.58, 95% CI: 1.03-2.43, P < 0.05; I2 = 47.7%). However, there was no significant difference between underweight and normal weight patients for major surgery-related complications such as anastomotic leakage, wound infection, and intra-abdominal infection. In addition, the short-term (RR: 2.12, 95% CI: 1.47-3.06, P < 0.001; I2 = 0%) and long-term survival (HR: 1.53, 95% CI: 1.14-2.07, P < 0.01; I2 = 64.0%) of underweight patients was significantly poorer than that of normal weight patients. CONCLUSION: Preoperative underweight status was significantly associated with unfavorable postoperative outcome of GC patients. The status may represent excessive nutritional consumption and malnutrition resulting from aggressive tumor.


Assuntos
Complicações Pós-Operatórias/etiologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Magreza , Humanos , Complicações Pós-Operatórias/mortalidade , Período Pré-Operatório
20.
Chem Commun (Camb) ; 53(99): 13213-13216, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29134225

RESUMO

We demonstrate an atomic scale TEM observation of shape evolutions of Pd nanocrystals under oxygen and hydrogen environments at atmospheric pressure. Combined with multi-scale structure reconstruction model calculations, the reshaping mechanism is fully understood.

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