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Metal-organic frameworks (MOFs) have emerged as promising novel therapeutics for treating malignancies due to their tunable porosity, biocompatibility, and modularity to functionalize with various chemotherapeutics drugs. However, the design and synthesis of dual-stimuli responsive MOFs for controlled drug release in tumor microenvironments are vitally essential but still challenging. Meanwhile, the catalytic effect of metal ions selection and ratio optimization in MOFs for enhanced chemodynamic therapy (CDT) is relatively unexplored. Herein, a series of MnFe-based MOFs with pH/glutathione (GSH)-sensitivity are synthesized and then combined with gold nanoparticles (Au NPs) and cisplatin prodrugs (DSCP) as a cascade nanoreactor (SMnFeCGH) for chemo-chemodynamic-starvation synergistic therapy. H+ and GSH can specifically activate the optimal SMnFeCGH nanoparticles in cancer cells to release Mn2+/4+ /Fe2+/3+ , Au NPs, and DSCP rapidly. The optimal ratio of Mn/Fe shows excellent H2 O2 decomposition efficiency for accelerating CDT. Au NPs can cut off the energy supply to cancer cells for starvation therapy and strengthen CDT by providing large amounts of H2 O2 . Then H2 O2 is catalyzed by Mn2+ /Fe2+ to generate highly toxic â¢OH with the depletion of GSH. Meanwhile, the reduced DSCP accelerates cancer cell regression for chemotherapy. The ultrasensitivity cascade nanoreactor can enhance the anticancer therapeutic effect by combining chemotherapy, CDT, and starvation therapy.
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Nanopartículas Metálicas , Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Ouro , Glutationa , Microambiente Tumoral , Nanotecnologia , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Peróxido de HidrogênioRESUMO
Transition-metal phosphates have been widely applied as promising candidates for electrochemical energy storage and conversion. In this study, we report a simple method to prepare a N, F co-doped mesoporous cobalt phosphate with rich-oxygen vacancies by in-situ pyrolysis of a Co-phosphate precursor with NH4 + cations and F- anions. Due to this heteroatom doping, it could achieve a current density of 10â mA/cm2 at lower overpotential of 276â mV and smaller Tafel slope of 57.11â mV dec-1 on glassy carbon. Moreover, it could keep 92 % of initial current density for 35â h, indicating it has an excellent stability and durability. Furthermore, the optimal material applied in supercapacitor displays specific capacitance of 206.3â F g-1 at 1â A â g-1 and maintains cycling stability with 80 % after 3000 cycles. The excellent electrochemical properties should be attributed to N, F co-doping into this Co-based phosphate, which effectively modulates its electronic structure. In addition, its amorphous structure provides more active sites; moreover, its mesoporous structure should be beneficial to mass transfer and electrolyte diffusion.
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Combined with computed tomography (CT), the laser absorption spectroscopy technique is used to measure the two-dimensional distribution information of the flow field. The CT method needs an "integral parameter" as a known quantity. The integrated absorbance satisfies the criterion in the laser absorption spectral measurement. The direct absorption spectroscopy method directly measures the integrated absorbance. However, fitting the absorbance curve is difficult due to the distorted baseline in harsh environments. By contrast, the wavelength modulation spectroscopy (WMS) method has satisfactory noise rejection capability. The difficulty that introduces WMS method to measure the non-uniform flow distribution is the integrated absorbance cannot be written in a mathematical expression. Previous efforts focused on solving the average temperature, concentration, and pressure and recalculating the integrated absorbance. This paper aims to develop an integrated absorbance measurement based on the calibration-free WMS method for non-uniform flow, which is called the calibration-free WMS-A method. First, the relationship between the transmissivity and integrated absorbance was established. Then, integrated absorbance was written into the WMS harmonic signals and solved by comparing the measured and simulated signals. The systematic comparison between the WMS-A and the previous WMS method showed the effectivity of the WMS-A method for non-uniform flow measurement. The reliable integrated absorbance can considerably improve the two-dimensional reconstruction quality.
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Two novel noncentrosymmetric metal borates, Ba2[B4O7(OH)2] (1) and Na[B5O7(OH)2](H2O) (2), have been obtained by hydrothermal and surfactant-thermal means. Compound 1 consists of novel one-dimensional borate chains formed by B3O9 and B3O8 rings, assembled into a three-dimensional (3D) framework by Ba2+ cations. The structure of 2 exhibits double-helical chains constructed from B5O10 primary building units, which are interconnected via Na+ cations and H-bonding interactions to generate a 3D framework. Second-harmonic-generation (SHG) measurements show that 1 shows a phase-matching powder SHG response of â¼2.2 × KH2PO4 (KDP), while 2 exhibits a weak SHG response. The cutoff edges of 1 and 2 are â¼242 and â¼221 nm, respectively, which suggests that they are potential ultraviolet nonlinear optical (NLO) materials. Band structures and NLO properties have also been theoretically studied.
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A new SHG material, namely, Pb2(BO3)(NO3), which contains parallel π-conjugated nitrate and borate anions, was obtained through a facile hydrothermal reaction by using Pb(NO3)2 and Mg(BO2)2â H2O as starting materials. Its structure contains honeycomb [Pb2(BO3)]∞ layers with noncoordination [NO3](-) anions located at the interlayer space. Pb2(BO3)(NO3) shows a remarkable strong SHG response of approximately 9.0 times that of potassium dihydrogen phosphate (KDP) and the material is also phase-matchable. The large SHG coefficient of Pb2(BO3)(NO3) arises from the synergistic effect of the stereoactive lone pairs on Pb(2+) cations and parallel alignment of π-conjugated BO3 and NO3 units. Based on its unique properties, Pb2(BO3)(NO3) may have great potential as a high performance NLO material in photonic applications.
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Metal ions have attracted a lot of interest in antitumor therapy due to their unique mechanism of action. However, multiple death mechanisms associate with metal ions to synergistic antitumors have few studies mainly due to the serious challenges in designing and building metal-associated multimodal treatment platforms. Hence, a series of glutathione-activatable CaCu-based metal-organic-frameworks loaded with doxorubicin and ovalbumin are successfully designed and synthesized with an "all in one" strategy, which is modified by galactosamine-linked hyaluronic acid to prepare multimodal treatment platform (SCC/DOX@OVA-HG) for targeted delivery and synergistic antitumor therapy. SCC/DOX@OVA-HG can be rapidly degraded by the overexpressed glutathione and then releases the "cargoes" in the tumor microenvironment. The released Cu+ efficiently catalyzes H2O2 to produce highly toxic ROS for CDT, and the up-regulation of calcium ion concentration in tumor cells induced by the released Ca2+ enables calcium overload therapy, which synergically enhances the metal-related death pattern. Meanwhile, OVA combined with Ca2+/Cu2+ further activates macrophages into an M1-like phenotype to accelerate tumor cell death through immunotherapy. Besides, the released DOX can also insert into the DNA double helix for chemotherapy. Consequently, the developed SCC/DOX@OVA-HG reveals significantly improved antitumor efficacy through a multimodal synergistic therapy of chemotherapy, chemodynamic therapy, calcium overload, and immunotherapy.
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Carcinoma Hepatocelular , Doxorrubicina , Neoplasias Hepáticas , Estruturas Metalorgânicas , Doxorrubicina/farmacologia , Doxorrubicina/química , Animais , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Camundongos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Ovalbumina/química , Cobre/química , Cobre/farmacologia , Ácido Hialurônico/química , Microambiente Tumoral/efeitos dos fármacosRESUMO
Four new layered silver(I) organoarsonates, namely, [Ag(3)(L(3))(CN)] (1) (H(2)L(3) = (PhAsO(2)H)(2)O), [Ag(3)(L(4))(CN)] (2) (H(2)L(4) = (2-NO(2)-C(6)H(4)-AsO(2)H)(2)O), [Ag(3)(HL(5))(H(2)L(5))] (3) (H(3)L(5) = 3-NO(2)-4-OH-C(6)H(3)-AsO(3)H(2)) and [Ag(2)(HL(5))] (4), were synthesized under solvothermal conditions. During the preparations of 1 and 2, condensation of organoarsonate ligands (H(2)L(1) = Ph-AsO(3)H(2); H(2)L(2) = 2-NO(2)-C(6)H(4)-AsO(3)H(2)) and the decomposition of acetonitrile molecules to cyanide anions occurred. Single crystals of H(2)L(4) ligand and compounds 1-4 were isolated, and their crystal structures have been determined by single crystal X-ray diffraction studies. In 1, the one-dimensional (1D) chains based on Ag(I) ions and {L(3)}(2-) anions are further interconnected by CN(-) into two-dimensional (2D) layers. In 2, adjacent Ag(I) ions within the silver(I) organoarsonate layer are further bridged by µ(4)-CN(-) anions with very short Ag···Ag contacts. In 3, the hexanuclear {Ag(6)O(12)} clusters are interconnected by bridging organoarsonate ligands into a silver(I) arsonate hybrid layer. In 4, the right-handed {Ag(4)O(4)} chains are further interconnected by organoarsonate ligands as well as additional Ag-O-Ag bridges into a novel silver(I) arsonate layer. Compounds 1 and 2 display red and orange-red emissions, respectively, which may be assigned to be an admixture of ligand-to-metal charge transfer (LMCT) and metal-centered (4d-5s/5p) transitions perturbed by Ag(I)···Ag(I) interactions. Upon cooling from room temperature to 10 K, compound 1 exhibits interesting temperature-dependent emissions.
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Using lead metaborate as starting material, by only adjusting pH values of the reaction systems, a series of lead(II) borates were obtained in high yields. The new polar material, namely, Pb2B3O5.5(OH)2 (1), crystallizes in the noncentrosymmetric space group Pnn2 of the orthorhombic system. Its structure features a novel three-dimensional (3D) anionic network with large 14 member rings (MRs) tunnels composed of unique one-dimensional (1D) chains and dimeric B2O7 fragments, both of which are built up from solely BO4 tetrahedra, and the Pb(2+) cations are located at the above 14-MRs tunnels. The synergistic effect of the stereoactive lone-pairs on Pb(2+) cations in 1 produces a strong SHG response of â¼3× KDP (KH2PO4) which is type I phase-matchable. The first example of lead(II) borate nitrate, namely, [Pb3(B3O7)](NO3) (2), crystallizes in space group Pnma, and its structures features a 3D lead(II) borate cationic network structure in which (B3O7)(5-) anions are bridged by lead(II) cations, the nitrate anions are isolated, and located at the small voids of the cationic network. Thermal stability and optical properties as well as theoretical calculations based on density functional theory (DFT) methods were also performed.
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The measurement of nonuniform temperature and concentration distributions was investigated based on tunable diode laser absorption spectroscopy technology. Through direct scanning multiple absorption lines of H2O, two zones for temperature and concentration distribution were achieved by solving nonlinear equations by least-square fitting from numerical and experimental studies. The numerical results show that the calculated temperature and concentration have relative errors of 8.3% and 7.6% compared to the model, respectively. The calculating accuracy can be improved by increasing the number of absorption lines and reduction in unknown numbers. Compared with the thermocouple readings, the high and low temperatures have relative errors of 13.8% and 3.5% respectively. The numerical results are in agreement with the experimental results.
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OBJECTIVE: To compare the results of application of Qu single abdominal aorta clamping for bloodless hepatectomy and Pringle hepatectomy in 118 cases of liver tumors. METHODS: The clinical data of 118 patients, including 59 patients undergoing Qu single abdominal aorta clamping for bloodless hepatectomy (Group QG) and 59 patients undergone Pringle first hepatic portal clamping hepatectomy (Group PG) since March 2009 in the Ningbo Tumor Hospital and Jiangxi Provincial Hospital were retrospectively reviewed. The changes of blood pressure, oxygen saturation, urine volume, intravenous fluid volume, amount of bleeding, time of abdominal aorta (or first hepatic portal) clamping, duration of operation and anesthesia, and other intraoperative indexes of the two groups were compared, and the changes of peritoneal drainage, blood tests, liver functions, etc. before operation and 1, 3, 7, 14 days after the hepatectomy in the two groups were also analyzed. RESULTS: After taking appropriate measures for intraoperative blood pressure control, only small fluctuations of blood pressure, which could be safely adjusted and controlled with stable vital signs, was observed in the group QG. The amount of intraoperative bleeding in the group QG was (96.25 ± 18.45) ml, significantly less than (536.25 ± 35.65) ml in the group PG (P < 0.05). In the group QG, both the duration of operation time [(227.58 ± 28.20) min] and duration of anesthesia [(249.48 ± 31.35) min] were significantly shorter than that [(261.46 ± 32.12) min and (286.58 ± 35.62) min, respectively] in the group PG (both P < 0.05). The postoperative liver dysfunction in the group QG was also milder than that in the group PG (P < 0.05). CONCLUSIONS: For liver tumor patients, Qu single abdominal aorta clamping for bloodless hepatectomy can basically achieve the goal of bloodless hepatectomy. This surgical operation is simple and safe, worthy of recommendation to skillful liver surgeons in hospitals there are some difficulties of blood supply.
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Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Adolescente , Adulto , Alanina Transaminase/sangue , Aorta Abdominal , Aspartato Aminotransferases/sangue , Perda Sanguínea Cirúrgica , Pressão Sanguínea , Carcinoma Hepatocelular/sangue , Constrição , Feminino , Hemangioma Cavernoso/sangue , Hemangioma Cavernoso/cirurgia , Humanos , Neoplasias Hepáticas/sangue , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Veia Porta , Estudos Retrospectivos , Albumina Sérica/metabolismo , Adulto JovemRESUMO
Objective: Dementia is a common and serious non-motor symptom in Parkinson's disease (PD). We aimed to investigate the reflexive saccade in PD patients and explore its potential role as a biomarker for cognitive decline. Methods: Using an infrared video-based eye tracker, we investigated reflexive saccades in 94 PD patients and 115 healthy controls (HCs). Saccadic parameters were compared between PD patients and HCs, and also among PD subgroups. The correlation of saccadic performance with disease duration, severity and cognition were further investigated. Results: Compared with healthy controls, PD patients had prolonged and hypometric reflexive saccades even in early disease stage. Univariate and multivariate analysis showed that there was significant inverse relation between prolonged latency and MMSE in PD patients (P < 0.05); tremor dominant PD patients were more likely to have decreased velocity than non-tremor-dominant PD patients (P < 0.05); saccadic accuracy was found to have no significant relation with disease duration, H&Y staging or MMSE. Conclusion: Reflexive saccadic performance was abnormal in PD and worsened with cognitive decline. The negative correlation between prolonged latency and MMSE scores may make the reflexive saccade a potential predictor for cognitive decline in Parkinson's disease.
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The development of high-efficient and cost-effective electrocatalysts is crucial to remove nitrate pollutant in wastewater. Herein, we design and prepare mesoporous Co-doped Cu2(OH)2CO3 malachite nanosheets as an electrocatalyst toward highly efficient nitrate reduction using a facile CO2 bubble-assisted coprecipitation synthesis. The electrocatalytic performance is subject to the Co/Cu ratio of this malachite. Remarkably, compared with the pristine monometal Cu or Co-based electrocatalyst, the optimal electrocatalyst, 0.3Co@Cu2(OH)2CO3, displays fast and highly efficient removal capacity of nitrate with an impressive high total nitrogen (TN) removal of 8628.99 mg N g-1CoCu (398.79 mg N gcat-1 h-1), N2 selectivity of 97.11% as well as negligible nitrite product at 100 mg L-1 NO3--N and 2000 mg L-1 Cl- neutral electrolyte. Above all, high total nitrogen removal efficiency (81.92%) and chemical oxygen demand (73.74%) in actual wastewater. Its excellent electrocatalytic performance is achieved by regulating the electronic structure and the adsorption/desorption of the intermediate. This study discovers a new type of electrode materials for nitrate removal in wastewater.
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The exfoliation of bulk two-dimensional metal-organic framework (MOF) into few-layered nanosheets has attracted much attention recently. In this work, an environmental-friendly route has been developed for layered-MOF (MAMS-1) delamination using deep eutectic solvent (DES), which is more sustainable and efficient alternative than conventional organic solvents for MOF nanosheet preparation. Under sonication condition, DES as solvents, the highest exfoliation rate of MAMS-1 is up to 70% with two host layers via poly(vinylpyrrolidone) (PVP) surfactant-assisted method. The presence of tert-butyl exteriors and the atomically thickness endow the MOF nanosheets stable suspension for at least one month. Due to the 2D structure and excellent stability, MAMS-1 nanosheet (MAMS-1-NS) was chosen as a good candidate to encapsulate Eu3+ cations. The obtained Eu3+@MAMS-1-NS acts as a multi-responsive luminescent sensor through fluorescence quenching, and can specifically recognize Fe3+ (LOD = 0.40 µM, KSV = 1.05 × 105 M-l), Hg2+ (LOD = 0.038 µM, KSV = 5.78 × 106 M-l), Cr2O72- (LOD = 0.33 µM, KSV = 1.55 × 105 M-l) and MnO4- (LOD = 0.088 µM, KSV = 4.49 × 105 M-l). Compared with bulk Eu3+@MAMS-1, the sensitivity of Eu3+@MAMS-1-NS is greatly improved owing to its ultrathin nanosheet morphology and highly accessible active sites on the surface.
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It remains a challenge to rational design of a new metal-organic framework (MOF) as highly efficient direct electrocatalysts for the oxygen evolution reaction (OER). Herein, we developed a simple and effective method to explore a new pillared-layered MOF with syringic acid as a promising OER electrocatalyst. The isostructural mono-, heterobimetallic MOF and N,S co-doped MOF by mixing thiourea were quickly synthesized in a high yield under solvothermal condition. Moreover, the optimized N,S co-doped MOF exhibits the lowest overpotential of 254â mV at 10â mA cm-2 on a glass carbon electrode and a small Tafel slope of 50â mV dec-1 , especially, this catalyst also possesses long-term electrochemical durability for at least 16â h. According to the characterization, the incorporation of N and S atoms into this heterobimetallic CoFe-based MOF could modify its pore structure, tune the electronic structure, accordingly, improve the mass and electron transportation, and facilitate the formation of active species, as a consequence, the improved activity of this new N,S co-doped MOF for OER should be mainly be ascribed to higher electrochemical activation toward the active species via inâ situ surface modification during the OER process.
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One-pot synthesis of a new doubly boron-doped polycyclic aromatic hydrocarbon of 6,12-dimesityl-6,12-dihydro-6,12-diboradibenzo[def,mno]chrysene (MDBDBC) was reported. MDBDBC features a rigid planar electron-deficient core structure and demonstrates good chemical and thermal stabilities. A low-lying LUMO of -3.53 eV, a low locally excited triplet energy of 1.92 eV, as well as green electroluminescence with maximum EQE of 4.9% were found for MDBDBC, suggesting its potential as an n-type unit for future organic light emitting diode applications.
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We report a simple first-principles-based simulation model (combining quantum mechanics with Marcus-Hush theory) that provides the quantitative structural relationships between angular resolution anisotropic hole mobility and molecular structures and packing. We validate that this model correctly predicts the anisotropic hole mobilities of ruberene, pentacene, tetracene, 5,11-dichlorotetracene (DCT), and hexathiapentacene (HTP), leading to results in good agreement with experiment.
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The development of nontoxic and stable all-inorganic perovskite nanocrystals (NCs) represents a major challenge to unlock widely practical applications in photoelectric fields. It is an effective strategy to discover nontoxic metal perovskite nanocrystals (NCs) with excellent optical properties. In addition, it has been proved that alkali metals such as rubidium (Rb) and potassium (K) have a good influence on improving the optical performance of perovskites. Hence, we reported new lead-free perovskite Rb7Bi3Cl16 single crystals, which displayed a zero-dimensional cluster structure and were composed of two kinds of octahedra with different distortions. At the same time, we synthesized its NCs, which showed a blue emission at 437 nm with a PLQY of 28.43% and presented a good optical and moisture stability for one month. The excellent moisture-stability might be attributed to their much higher ratio of Rb atoms and the ideal [BiCl6]3- octahedra on the surface, which are beneficial to form an inorganic BiOCl shell to protect the Rb7Bi3Cl16 NCs from moisture attack.
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The main commercial infrared nonlinear optical (IR NLO) crystals, typically, AgGaS2, have some inherent disadvantages, for example, low laser damage threshold (LDT) or relatively poor stability, which limit their wide application. Here, we discover two new IR optical perovskites based on 1,4-diazabicyclo[2,2,2]octane, namely, (H2dabco)(PbCl3)2 (1) and (H2dabco)(H2PbBr6)·H2O (2). 1 and 2 crystallize in the noncentrosymmetric space groups P43212 and P63mc, respectively, displaying a broad transparent range with high transmission. Particularly, compound 2 exhibits a moderate SHG response of 1.8 times that of KH2PO4 (KDP) at 1064 nm with a high laser-induced damage threshold of 328.8 MW cm-2, indicating that it is a new promising NLO material.
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Two new alkali boroselenites RbSe3B2O9(OH) and CsSe3B2O9(OH) have been synthesized by traditional solid-state reactions. Single-crystal X-ray diffraction study indicated that they are isostructural and adopt a new type of structure, which crystallizes in the noncentrosymmetric space group P212121. Optical diffuse reflectance spectrum studies emphasized that both are indirect optical transitions with values of 3.79 and 4.17 eV for RbSe3B2O9(OH) and CsSe3B2O9(OH), respectively. Optical analysis revealed a broad transparency window in the 0.3-8.5 µm region for both compounds. In addition, RbSe3B2O9(OH) featured a relatively weak second-harmonic-generation response, and for CsSe3B2O9(OH), the response is 0.8-times that of KH2PO4. Theoretical calculations of band structure, density of state, and linear and nonlinear optical properties were also performed to get insight into the relationships between electronic structures and their optical properties.
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Herein, unprecedented NLO-brominated tin hypophosphites, namely [Sn2(H2PO2)3]Br, were discovered via a facile surfactant-induced method, which displayed a moderate powder SHG intensity (3.0 × KDP) in type - I phase matching behavior. This complex has high chemical and thermal stability at room temperature. DFT calculations and SHG coefficient analyses revealed that the alignment of the SHG-active-units SnO3 trigonal pyramids and Br- anions in its structure mainly contribute to the macroscopical SHG behaviors.