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1.
Langmuir ; 39(38): 13409-13419, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37703076

RESUMO

In this Perspective, mainly based on the model of structural water molecules (SWs) as bright color emitters, we briefly summarize the development and theoretical elaboration of P-band intermediate state (PBIS) theory as well as its application in several typical catalytic redox reactions. In addition, with a simple equation (2∫ψ2σ1' + ∫ψ2σ2 + ∫ψ2π = 1), we clearly define how the interface states correlate with the three basic parameters of heterogeneous catalysis (conversion, selectivity, and stability), and what is the dynamic nature of catalytic active sites. Overall, the proposal of SW-dominated PBIS theory establishes an internal physical connection between the decay kinetics of excited electrons and the catalytic reaction kinetics and provides new insights into the physical origin of photoluminescence emission of low-dimensional quantum nanodots and the physical nature of nanoconfinement and nanoconfined catalysis.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(1): 18-24, 2021 Jan.
Artigo em Zh | MEDLINE | ID: mdl-33476532

RESUMO

OBJECTIVE: To study the safety of two ventilator weaning strategies after high-frequency oscillatory ventilation (HFOV) for the treatment of neonatal respiratory distress syndrome (NRDS) in preterm infants. METHODS: A prospective randomized controlled trial was conducted for 101 preterm infants with NRDS, with a gestational age of ≤32+6 weeks or a birth weight of ≤1 500 g, who were admitted to the neonatal intensive care unit of Xiamen Maternal and Child Health Hospital from January 1, 2019 to June 30, 2020. The infants underwent HFOV as the preferred treatment. The infants were randomly divided into an observation group (50 infants with direct weaning from HFOV) and a control group (51 infants with weaning after HFOV was switched to conventional mechanical ventilation). The two groups were compared in terms of failure rate of ventilator weaning within 72 hours, changes in blood gas parameters at 2 hours before weaning and at 2 and 24 hours after weaning, respiratory support therapy, incidence rates of complications, and outcome at discharge. RESULTS: There was no significant difference in the failure rate of ventilator weaning within 72 hours (8% vs 14%, P > 0.05). The observation group had a significantly shorter duration of mechanical ventilation than the control group [(64±39) hours vs (88±69) hours, P < 0.05]. There were no significant differences between the two groups in the duration of mechanical ventilation, total oxygen supply time, blood gas parameters before and after ventilator weaning, incidence rates of complications, and outcome at discharge (P > 0.05). CONCLUSIONS: For preterm infants with NRDS, the strategy of weaning directly from HFOV is safe and reliable and can reduce the duration of invasive mechanical ventilation, and therefore, it holds promise for clinical application.


Assuntos
Ventilação de Alta Frequência , Síndrome do Desconforto Respiratório do Recém-Nascido , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estudos Prospectivos , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Desmame do Respirador
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(9): 889-895, 2021.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34535202

RESUMO

OBJECTIVES: To investigate the incidence of maternal group B Streptococcus (GBS) colonization and neonatal early-onset GBS disease (GBS-EOD), and to study the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. METHODS: A total of 16 384 pregnant women and 16 634 neonates delivered by them were enrolled prospectively who had medical records in Xiamen Maternal and Child Care Hospital, Beijing Obstetrics and Gynecology Hospital of Capital Medical University, and Zhangzhou Zhengxing Hospital from May 1, 2019 to April 30, 2020. Unified GBS screening time, culture method, and indication for intrapartum antibiotic prophylaxis (IAP) were adopted in the three hospitals. The incidence rates of maternal GBS colonization and neonatal GBS-EOD were investigated. A multivariate logistic regression analysis was used to identify the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. RESULTS: In these three hospitals, the positive rate of GBS culture among the pregnant women in late pregnancy was 11.29% (1 850/16 384), and the incidence rate of neonatal GBS-EOD was 0.96‰ (16/16 634). The admission rate of live infants born to the GBS-positive pregnant women was higher than that of those born to the GBS-negative ones (P<0.05). The live infants born to the GBS-positive pregnant women had a higher incidence rate of GBS-EOD than those born to the GBS-negative ones [6.38‰ (12/1 881) vs 0.27‰ (4/14 725), P<0.05]. The multivariate logistic regression analysis showed that placental swabs positive for GBS and positive GBS in neonatal gastric juice at birth were independent predictive factors for the development of GBS-EOD (P<0.05), while adequate IAP was a protective factor (P<0.05) in the offspring of pregnant women with GBS colonization. CONCLUSIONS: GBS colonization of pregnant women in late pregnancy has adverse effects on their offspring. It is important to determine prenatal GBS colonization status of pregnant women and administer with adequate IAP based on the indications of IAP to reduce the incidence of neonatal GBS-EOD. Citation.


Assuntos
Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Antibioticoprofilaxia , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Placenta , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Estudos Prospectivos , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(12): 1234-1238, 2019 Dec.
Artigo em Zh | MEDLINE | ID: mdl-31874666

RESUMO

Neonatal respiratory failure is a serious clinical illness commonly seen in the neonatal intensive care unit (NICU). Although clinicians want to maximize noninvasive respiratory support, some low-birth-weight preterm infants may require invasive respiratory support from the beginning. As an important respiratory management technique for the treatment of respiratory failure, high-frequency oscillatory ventilation (HFOV) allows gas exchange by rapid delivery at a tidal volume lower than or equal to anatomy death volume. Continuous distending pressure was applied to achieve uniform lung expansion, reduce repeated contraction of lung tissue, and exert a protective effect on lung tissue, and so it is preferred by clinicians and has been widely used in clinical practice. However, no consensus has been reached on the methods for weaning from HFOV. This article reviews the methods for weaning from HFOV, so as to provide help for clinical practice.


Assuntos
Ventilação de Alta Frequência , Doenças do Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ventilação com Pressão Positiva Intermitente
5.
ACS Appl Mater Interfaces ; 14(28): 32665-32674, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35797527

RESUMO

A bias-selectable photodetector, which can sense the wavelength of interest by tuning the polarity of applied bias, is useful for target discrimination and identification applications. So far, those detectors are generally based on the back-to-back photodiode configuration via exploiting epitaxial semiconductors as optoelectronic materials, which inevitably lead to high fabrication costs and complex device architectures. Here, we demonstrate that our band-engineered van der Waals heterostructures can be applied as bias-selectable photodetectors. Our first prototypical device is mainly composed of black phosphorus (BP) and MoTe2 light absorbers sandwiching a thin MoS2 hole blocking layer. By varying the bias polarity, its spectral photoresponse can be switched between near-infrared and short-wave infrared bands, and our optoelectronic characterizations indicate that the detector can exhibit high external quantum efficiency (EQE) and fast operation speed. With this framework, we further demonstrate the detector with bias-selectable photoresponses within the mid-wave infrared band using BP/MoS2/arsenic-doped BP heterostructures and show that our developed detectors can be integrated into a single-pixel imaging system to capture dual-band infrared imaging.

6.
Chemistry ; 17(50): 14258-66, 2011 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-22068981

RESUMO

Following the structural concept of copper-containing proteins in which dinuclear copper centers are connected by hydroxide bridging ligands, a bidentate copper(II) complex has been incorporated into nano-confined MCM-41 silica by a multistep sequential grafting technique. Characterization by a combination of EPR spectroscopy, X-ray photoelectron spectroscopy (XPS), UV/Vis spectroscopy, IR spectroscopy , and solid-state (13)C and (29)Si cross-polarization magic-angle spinning (CP-MAS) NMR suggests that dinuclear Cu complexes are bridged by hydroxide and other counterions (chloride or perchlorate ions), similar to the situation for EPR-undetectable [Cu(II)···Cu(II)] dimer analogues in biological systems. More importantly, a dynamic mononuclear-dinuclear equilibrium between different coordination modes of copper is observed, which strongly depends on the nature of the counterions (Cl(-) or ClO(4)(-)) in the copper precursor and the pore size of the silica matrix (the so-called confinement effect). A proton-transfer mechanism within the hydrogen-bonding network is suggested to explain the dynamic nature of the dinuclear copper complex supported on the MCM-41 silica.


Assuntos
Cobre/química , Compostos Organometálicos/química , Dióxido de Silício/química , Catálise , Cristalografia por Raios X , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectroscopia Fotoeletrônica , Prótons , Espectrofotometria Ultravioleta
7.
J Oncol ; 2021: 2939162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539781

RESUMO

INTRODUCTION: Stage IIB cervical cancer (CC) is an advanced stage CC with poor prognosis. Inflammatory response plays a crucial role in the development of CC, and systemic inflammatory indexes were related to the prognosis in several cancers. The objective of the study was to determine the prognostic value of platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), basophil-to-lymphocyte ratio (BLR), and systemic inflammation response index (SIRI) as inflammatory indexes in patients with stage IIB CC. MATERIALS AND METHODS: A retrospective study was performed in 260 patients with stage IIB CC. PLR, NLR, MLR, BLR, and SIRI were obtained from routine blood tests. Prognosis information of the patients was acquired from regular clinical follow-up. Recurrence and response to therapy were determined through electronic medical records (EMRs). Correlations of the inflammatory indexes with overall survival (OS), progression-free survival (PFS), recurrence, and response to therapy were analyzed using SPSS version 26.0 software. RESULTS: Receiver operating characteristic (ROC) curve analyses suggested that NLR, MLR, and SIRI had better predictive value than PLR as well as BLR in the prognosis and recurrence risk. Both univariate and multivariate survival analyses showed that higher NLR and MLR were significantly associated with shorter OS as well as PFS, whereas SIRI was not an independent predictive factor of PFS. Chi-square test results revealed that increased NLR was significantly correlated with higher recurrence rate (P=0.046), and increased MLR showed significant correlation with elevated recurrence risk (P=0.002). Univariate and binary logistic regression analyses for response to therapy indicated that elevated NLR was associated with decreased complete remission (CR) rate (P=0.031), and the P value lost statistical significance while being adjusted by tumor size (P=0.108). CONCLUSIONS: For patients with stage IIB CC, both NLR and MLR are independent prognostic factors as well as risk factors for recurrence; NLR serves as a potential marker for therapeutic response.

8.
Langmuir ; 26(16): 13493-501, 2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20695596

RESUMO

The accessibility of metal(II) complexes in 2D hexagonal mesostructured porous silicas obtained by direct synthesis is controlled using an appropriate organosilane ligand. This is exemplified here using copper(II) as a transition metal probe and a neutral or negatively charged ligand: N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, L(A), and, N-salicylaldimine-propylamine-trimethoxysilane, L(B)(-), respectively. L(A) leads to inaccessible complexes located into the pore wall and called "embedded" sites here where silanolate groups from the siliceous network block the access to Cu(II) ions. By contrast, L(B)(-) generates accessible complexes, named "showing-on" sites here. The copper-containing silicas were synthesized with various metal molar ratios (M/SiO(2) = 0.5-3%) in basic media, with cetyltrimethylammonium p-toluenesulfonate (CTATos) as template and with sodium silicate solution as silicon source. A soft template extraction procedure has been developed to preserve the complex integrity of the showing-on copper sites during the treatment. The embedded copper(II) and nickel(II) sites were compared. Materials containing embedded, showing-on, and grafted sites were also compared with regard to pore size, surface polarity, and metal leaching. The material containing showing-on sites was found to be catalytically active for the hydroxylation of phenol into catechol and hydroquinone. Both textural and structural properties of the material and the copper sites were investigated using XRD, TEM, N(2) sorption isotherms, TGA, FT-IR, UV-visible, and EPR spectroscopies.

9.
Gulf J Oncolog ; 1(26): 67-71, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29607827

RESUMO

BACKGROUND: Vaginal metastases originating from renal cancer remain a rare event, with less than 100 cases reported in the literature. The spreading mechanism is still under scrutiny. The tumoral bleeding often is a symptom revealing vaginal metastases. CASE: The present work reports patient case having vaginal metastasis of renal clear-cell cancer. The vaginal metastasis was treated by a 3-D conformational radiotherapy. Our experience is discussed with respect to an updated literature review concerning the medical management of vaginal metastasis related to kidney cancer. CONCLUSION: In our case, a 15 Gy hypofractionatedradiotherapy is efficient to control bleeding on the vaginal metastases of the kidney cancer. To add up a 15 Gy hypofractionated-radiotherapy in 5 fractions is an option if bleeding is still present. The tolerance of the treatment is excellent and no side effects have been described.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Neoplasias Vaginais/secundário , Idoso , Carcinoma de Células Renais/radioterapia , Feminino , Humanos , Neoplasias Renais/radioterapia , Prognóstico , Hipofracionamento da Dose de Radiação , Neoplasias Vaginais/radioterapia
10.
Crit Rev Oncol Hematol ; 131: 96-101, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30293712

RESUMO

Triple-negative breast cancer (TNBC) (estrogen receptor-negative, progesterone receptor-negative, and HER2-negative) is viewed as an aggressive subgroup of breast cancer. Treating patients with TNBC remains clinically challenging. It's now well established than radiation therapy is able to improve locoregional control in breast cancer patients both after breast conserving surgery or mastectomy, with positive impact in high-risk patients for long-term survival. Biologic characterization of breast tumor different subtypes, in particular the heterogeneous subtype of TNBC could permit to adapt the treatment plan. In the present review, summarizing the molecular types, we describe clinical features and postoperative radiotherapy current situation for TNBC, and we provide new strategies and directions through an adapted radiation therapy.


Assuntos
Radioterapia , Neoplasias de Mama Triplo Negativas/radioterapia , Feminino , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/patologia
11.
Radiat Oncol ; 13(1): 16, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29394940

RESUMO

BACKGROUND: Despite screening campaigns, cervical cancers remain among the most prevalent malignancies and carry significant mortality, especially in developing countries. Most studies report outcomes of patients receiving the usual standard of care. It is possible that these selected patients may not correctly represent patients in a real-world setting, which may be a limitation in interpreting outcomes. This study was undertaken to identify prognostic factors, management strategies and outcomes of locally advanced cervical cancers (LACC) treated in daily clinical practice. METHODS: Medical files of all consecutive patients treated with curative intent for LACC in a French Cancer Care Center between 2004 and 2014 were reviewed retrospectively. RESULTS: Ninety-four patients were identified. Performance status was ≥ 2 in 10.6%. Median age at diagnosis was 63.0. Based on the International Federation of Gynecology and Obstetrics classification, tumours were classified as follows: 10.6% IB2, 22.3% IIA, 51.0% IIB, 4.3% IIIA and 11.7% IIIB. Pelvic lymph nodes were involved in 34.0% of cases. Radiotherapy was delivered for all patients. Radiotherapy technique was intensity modulated radiation therapy or volumetric modulated arc therapy in 39.4% of cases. A concurrent cisplatin chemotherapy was delivered in 68.1% of patients. Brachytherapy was performed in 77.7% of cases. The recommended standard care (concurrent chemoradiotherapy with at least five chemotherapy cycles during radiotherapy, followed by brachytherapy) was delivered in 43.6%. The median overall treatment time was 56 days. Complete tumour sterilisation was achieved in 55.2% of cases. Mean follow-up was 54.3 months. Local recurrence rate was 18.1%. Five-year overall survival was 61.9% (95% Confident Interval (CI) = 52.3-73.2) and five-year disease-specific survival was 68.5% (95% CI = 59.2-79.2). Poor performance status, lymph nodes metastasis and absence of concurrent chemotherapy were identified as poor prognostic factors in multivariate analysis. CONCLUSIONS: Less than 50% of patients received the standard care. Because LACC patients and disease are heterogeneous, treatment tailoring appears to be common in current clinical practice. However, guidelines for tailoring management are not currently available. More data about real-world settings are required in order to to optimise clinical trials' aims and designs, and make them translatable in daily clinical practice. TRIAL REGISTRATION: retrospectively registered.


Assuntos
Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Quimiorradioterapia/métodos , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/mortalidade
13.
Chem Commun (Camb) ; (4): 407-9, 2007 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-17220986

RESUMO

One-dimensional zigzag coordination chains in four different directions are hierarchically entangled to generate an unprecedented 3D interwoven framework, which exhibits permanent porosity and guest selectivity.

14.
Dalton Trans ; 46(20): 6692-6699, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28484777

RESUMO

The poor hydrothermal stability of germanosilicate zeolites greatly retards their industrial application. Herein, we present a direct synthesis of Ge-containing IWR zeolites with outstanding hydrothermal stability. A simple quaternary ammonium cation, diethyldimethylammonium, was used as the structure-directing agent for the first time. The structure and chemical composition of the framework was studied by performing Rietveld refinement of XRD data combined with electron microscopy, thermogravimetric and chemical analysis techniques. Al-free and Al-containing IWR zeolites were subjected to high-temperature vapor (973 K, 4 h), water-immersion (room temperature, 12 h) and treatment with 65% HNO3 solution (423 K, 24 h) to test their hydrothermal stability. Materials before and after hydrothermal treatments were characterized by complementary methods (XRD, FTIR, NMR and N2 sorption). The set of experimental data unambiguously proves the high stability of the zeolite framework.

15.
Chem Commun (Camb) ; 51(8): 1449-52, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25487895

RESUMO

In the synthesis of polyoxymethylene dimethyl ethers (PODEn) catalyzed by ordered supermicroporous aluminosilicates, shape selectivity was observed and the high selectivity for target products (PODE3-8) was attributed to the particular pore diameter.

16.
Asian Pac J Cancer Prev ; 16(9): 3945-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25987066

RESUMO

BACKGROUND: For brachytherapy of cervical cancer, applicator shifts can not be avoided. The present investigation concerned Utrecht interstitial applicator shifts and their effects on organ movement and DVH parameters during 3D CT-based HDR brachytherapy of cervical cancer. MATERIALS AND METHODS: After the applicator being implanted, CT imaging was achieved for oncologist contouring CTVhr, CTVir, and OAR, including bladder, rectum, sigmoid colon and small intestines. After the treatment, CT imaging was repeated to determine applicator shifts and OARs movements. Two CT images were matched by pelvic structures. In both imaging results, we defined the tandem by the tip and the base as the marker point, and evaluated applicator shift, including X, Y and Z. Based on the repeated CT imaging, oncologist contoured the target volume and OARs again. We combined the treatment plan with the repeated CT imaging and evaluated the change range for the doses of CTVhr D90, D2cc of OARs. RESULTS: The average applicator shift was -0.16 mm to 0.10 mm for X, 1.49 mm to 2.14 mm for Y, and 1.9 mm to 2.3 mm for Z. The change of average physical doses and EQD2 values in Gyα/ß range for CTVhr D90 decreased by 2.55 % and 3.5 %, bladder D2cc decreased by 5.94 % and 8.77 %, rectum D2cc decreased by 2.94 % and 4 %, sigmoid colon D2cc decreased by 3.38 % and 3.72 %, and small intestines D2cc increased by 3.72 % and 10.94 %. CONCLUSIONS: Applicator shifts and DVH parameter changes induced the total dose inaccurately and could not be ignored. The doses of target volume and OARs varied inevitably.


Assuntos
Braquiterapia/instrumentação , Carcinoma de Células Escamosas/radioterapia , Imageamento Tridimensional/métodos , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X/métodos , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Braquiterapia/métodos , Carcinoma de Células Escamosas/patologia , Colo Sigmoide/efeitos da radiação , Feminino , Humanos , Pessoa de Meia-Idade , Órgãos em Risco , Prognóstico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Bexiga Urinária/efeitos da radiação , Neoplasias do Colo do Útero/patologia
17.
Phys Chem Chem Phys ; 11(16): 2912-21, 2009 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-19421506

RESUMO

The molecular stencil patterning (MSP) technique is a new surface molecular engineering technique developed for cation-templated porous silicas to graft several functions with vicinity control. First, tetramethylammonium ions (TMA(+)) are introduced by ion exchange of the cetyltrimethyl-ammonium template (CTA(+)). Then, the coverage is controlled to create a masking array of cations, the pattern of which is produced by mutual electrostatic repulsion. A first function is grafted, here monopodal trimethylsilyl groups (TMS) or dipodal ethyl-1,2-bis(dimethylsilyl) (EBDMS) groups. After the removal of the masking cations, a second function is grafted using here N-(2-aminoethyl)-3-amino-propyltrimethoxysilane precursor. The distribution of N-(2-aminoethyl)-3-amino-propylsilyl functions (AAPS) is probed by complexation to Cu(ii) ions. X-Ray diffraction, N(2) adsorption-desorption isotherms, (13)C solid-state NMR, IR, UV-visible and electron paramagnetic resonance (EPR) techniques show that MSP can produce isolation of AAPS by TMS, or even better by EBDMS groups, with preservation of the silica pore structure.

18.
Inorg Chem ; 44(24): 8822-35, 2005 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-16296837

RESUMO

Four new inorganic-organic hybrid coordination polymers in which 1D or 2D manganese(II) azido inorganic motifs are interlinked into higher-dimensional networks have been synthesized by use of a series of bis(pyridyl)-type organic bridging ligands (linkers) with different side groups and/or different coordination orientations. The dimensionality and the topology of the manganese(II) azido motif and the whole structure are sensitive to the organic linkers used. Compounds 1 and 3 are 3D coordination polymers with pillared-layer architectures: in 1, 2D Mn(II) layers with alternate double end-on (EO) and single end-to-end (EE) azido bridges are pillared by zigzag organic linkers, and 3 is built from single EE azido-bridged Mn(II) layers and linear organic linkers. The 3D nets of 1, 3, and related compounds have been related to the specific length and coordination orientation of the organic pillars and the undulate shape of the manganese(II) azido layers. Consistent with their structures, both 1 and 3 exhibit weak ferromagnetism due to spin canting. Compound 1 is a weak ferromagnet with T(c) = 16 K, and 3 is a metamagnet with T(c) = 23 K. On the other hand, compounds 2 and 4 are 2D coordination networks in which 1D manganese(II) azido chains are interlinked by organic linkers: 2 is the first 2D network built from Mn(II) chains with alternate double EE and double EO azido bridges, which mediate antiferro- and ferromagnetic interactions, respectively; 4 is the first 2D network built from Mn(II) chains with only single EE azido bridges, which mediate antiferromagnetic interactions. The magnetic susceptibility of 4 exhibits a rapid rise at very low temperature, which may be attributed to paramagnetic impurities or spin canting.

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