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OBJECTIVE: To compare the outcome of the laparotomy-assisted endoscopic removal (LAER) of gastrointestinal foreign bodies (FBs) with traditional enterotomy, and to determine which factors affected the ability to remove FBs. STUDY DESIGN: Retrospective observational study. SAMPLE POPULATION: Dogs and cats (n = 81) with gastrointestinal FBs. METHODS: Dogs and cats were divided into Group 1 (LAER, n = 40) and Group 2 (Enterotomy, n = 41). The localization and characteristics of the FBs (sharp or blunt; discrete or linear; single or multiple) were evaluated statistically to identify the factors that affected the ability of LAER to remove, partially or completely, the FBs (χ2 test). The length of the postoperative stay, postoperative analgesia, and resumption of spontaneous feeding were compared between groups (Mann-Whitney U-test). Short-term follow up (14 days) was recorded. RESULTS: Laparotomy-assisted endoscopic removal allowed complete or partial removal of FBs in 35/40 dogs and cats, regardless of the characteristics or the localization of the FBs. The presence of intestinal wall damage (p = .043) was associated with the conversion to an enterotomy. Group 1 required a shorter postoperative hospital stay (p = .006), less need for analgesia (p < .001), and experienced a faster resumption of spontaneous feeding (p = .012), and similar complication rate to Group 2. CONCLUSION: Laparotomy-assisted endoscopic removal resulted in a faster postoperative recovery when compared with an enterotomy. The FBs' characteristics or localization did not affect the efficacy of the technique to remove FBs. CLINICAL SIGNIFICANCE: Laparotomy-assisted endoscopic removal allows the removal of a variety of FBs, avoiding intestinal incision and resulting in a fast postoperative recovery.
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Doenças do Gato , Doenças do Cão , Corpos Estranhos , Laparotomia , Animais , Cães/cirurgia , Gatos/cirurgia , Estudos Retrospectivos , Doenças do Cão/cirurgia , Feminino , Masculino , Laparotomia/veterinária , Doenças do Gato/cirurgia , Corpos Estranhos/veterinária , Corpos Estranhos/cirurgia , Trato Gastrointestinal/cirurgia , Resultado do TratamentoRESUMO
Lymph node (LN) metastasis in canine mast cell tumor (MCT) can affect prognosis and postsurgical treatment recommendations; however, routine histological single-section examination may underestimate the incidence of metastases. This prospective study aimed at determining whether longitudinal step-sectioning of the entire LN allows for a more reliable detection of metastases. Dogs with MCT undergoing resection of the primary tumor and regional lymphadenectomy were enrolled. Formalin-fixed LNs were bisected longitudinally, both halves were embedded in paraffin and histological sections prepared at 200 µm steps. The nodal mast cells were classified according to the Weishaar classification. First-section evaluation (FSE; ie, examination of the first section obtained from the blocks) and whole LN step-section evaluation (SSE) were compared. Fifty-eight LNs were included. The median number of sections per LN was 6 (range, 3-28). FSE with toluidine blue (TB) revealed 27 (47%) nonmetastatic (HN0), 14 (24%) premetastatic (HN1), 9 (15%) early metastatic (HN2), and 8 (14%) overtly metastatic (HN3) LNs. SSE with TB resulted in upgrading the LN status in 2 cases (HN2 to HN3; HN0 to HN1). Evaluation of the first section plus an additional step-section resulted in 100% accuracy. Compared with SSE with TB, the accuracy of FSE with HE was 98% for HN3 LNs and 74% for HN2 LNs. FSE appears to reliably allow for the detection of LN metastasis in MCT, although examination of a further parallel section at a 200 µm step may increase the accuracy. A metachromatic stain is recommended for the identification of early metastases.
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Doenças do Cão , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Excisão de Linfonodo/métodos , Excisão de Linfonodo/veterinária , Linfonodos/patologia , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Estadiamento de Neoplasias , Estudos ProspectivosRESUMO
A 2 mo old domestic shorthair kitten was presented for acute respiratory distress and severe ambulatory difficulties. Thoracic radiography revealed hyperinflation of the left cranial lung lobe and a mass with soft-tissue/gas opacity in the caudal mediastinum, leading to the suspicion of congenital lung lobe emphysema and hiatal hernia. Decreased bone radiopacity and suspected pathological fractures were also present. Complete clinicopathological analyses showed significant ionized hypocalcemia and suspicion of secondary hyperparathyroidism related to an inadequate diet. Lung lobectomy and reduction of the hiatal hernia following a median sternotomy and a cranial laparotomy were performed. IV and oral supplementation of calcium led to a full recovery and improvement in the kitten's walking. A histopathological analysis revealed pulmonary emphysema associated with hypoplastic and irregular bronchial cartilage. Congenital lobar emphysema is a rare disease in both humans and animals. This is the first veterinary report describing a kitten affected by congenital lobar emphysema combined with a hiatal hernia and additionally complicated by secondary nutritional hyperparathyroidism with a good long-term outcome.
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Doenças do Gato , Hérnia Hiatal , Hiperparatireoidismo Secundário , Enfisema Pulmonar , Animais , Gatos , Feminino , Hérnia Hiatal/complicações , Hérnia Hiatal/cirurgia , Hérnia Hiatal/veterinária , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/cirurgia , Hiperparatireoidismo Secundário/veterinária , Pulmão/anormalidades , Pulmão/patologia , Pulmão/cirurgia , Enfisema Pulmonar/congênito , Enfisema Pulmonar/cirurgia , Enfisema Pulmonar/veterináriaRESUMO
An 11 yr old male Drahthaar dog was presented for dysuria, pollakiuria, and history of uroliths. Abdominal ultrasound revealed a subcapsular fluid-filled lesion of the left kidney, suspected cholecystitis, and a splenic infarct. The renal lesion was fully drained and cytology of the renal subcapsular and perirenal fluids revealed septic exudate. Bacterial culture of the urine, bile, and perirenal and subcapsular fluids were all positive for Staphylococcus pseudintermedius. Antimicrobial therapy was instituted based on culture sensitivity. After 7 days the dog re-presented for vomiting and abdominal pain, and a focal intestinal injury was suspected based on abdominal ultrasound. Enterectomy of an ischemic jejunal loop, a partial splenectomy, and excision of the left renal subcapsular abscess were performed. The renal parenchyma was left intact. Histopathology confirmed the diagnosis of a renal subcapsular abscess, intestinal infarction, and focal pyogranulomatous splenitis. Cholecystitis was confirmed by bile cytology and culture. No major complications and no recurrences were encountered at 1 yr follow-up. This is the first report of a renal subcapsular abscess in the dog, with septic complications, and treated with a kidney-sparing surgery.
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Abscesso/veterinária , Doenças do Cão/cirurgia , Nefropatias/veterinária , Infecções Estafilocócicas/veterinária , Staphylococcus/isolamento & purificação , Abscesso/tratamento farmacológico , Abscesso/microbiologia , Abscesso/cirurgia , Animais , Antibacterianos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Nefropatias/cirurgia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/cirurgiaRESUMO
The aim of this study was to describe the anatomic locations and treatments available for deeply located vegetal foreign bodies in cats. Ten cases of migrating vegetal foreign bodies (vFBs) requiring surgical removal are reported. The diagnoses of vFBs in the thoracic cavity (4/10), retroperitoneal space (2/10), and paratracheal region (1/10) were obtained by ultrasound examination; however, in the perineum or penile urethra (2/10) and peritoneum (1/10), the vFBs were found during surgery. Intraoperative ultrasound guidance helped remove vFBs from the retroperitoneal space and paratracheal tissues. Clinical signs resolved in 8 out of 10 cases, 1 out of 10 cases had recurrent draining fistula, and 1 out of 10 was euthanized for ethical reasons. The intrathoracic was the most common location in the present study, followed by retroperitoneal space and urethra/perineum. Ultrasound guidance was essential for the diagnosis and/or treatment of vFBs located in the thoracic, retroperitoneal, and cervical regions.
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Doenças do Gato/patologia , Corpos Estranhos/veterinária , Migração de Corpo Estranho/veterinária , Animais , Doenças do Gato/cirurgia , Gatos , Feminino , Corpos Estranhos/patologia , Corpos Estranhos/cirurgia , Migração de Corpo Estranho/cirurgia , Masculino , Estudos RetrospectivosRESUMO
The relationships between the photophysics and structural properties of 4,7-dithien-2-yl-2,1,3-benzothiadiazole as a function of solvent polarity are investigated both experimentally and by computational methods. Stationary fluorescence measurements are consistent with a model envisaging the presence of three types of conformers in equilibrium in the ground state. They are characterized by different relative orientations of the thiophene rings. Due to a low rotational barrier, the sample in solution is characterized by a distribution of relative internal orientations. By applying the Kawski method, we evaluate the average dipole moment of ground and excited states of the three types of conformers. The ground state dipole moments are small and similar for the three types of conformers. On the contrary, dipole moments differ substantially in the excited state. X-ray diffraction of a single crystal confirms the presence of an orientational disorder of thiophene rings. Transient absorption UV-visible spectroscopy experiments allows the identification of the main mechanisms responsible for the large Stokes shift observed in this push-pull molecule. Time dependent spectra provide a picture of the relaxation processes occurring after excitation: the primary step is an internal charge transfer assisted by thiophene ring planarization which occurs on a time scale ranging from 0.88 to 1.3 picoseconds depending on solvent polarity. Moreover, time-resolved fluorescence measurements are consistent with a mechanism involving planarization accompanied by a stabilization of the charge transfer state as observed in polar solvents. In the latter, longer fluorescence lifetimes are observed along with a quantum yield decrease due to the activation of specific non-radiative relaxation channels. The photophysical behavior of 4,7-dithien-2-yl-2,1,3-benzothiadiazole in a solid matrix of polymethyl methacrylate is similar to that observed in solution, but the overall non-radiative process rate is slow with respect to that in the liquid phase. As a consequence, the radiative processes are enhanced giving rise to a fluorescence quantum yield of 90%. Such behavior is consistent with the proposed relaxation model.
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BACKGROUND: Neoadjuvant chemotherapy (NAC) is delivered before surgery to allow less extensive tumour resection, but the optimal surgical margin width after NAC is unknown. The aim of this study was to determine the impact of reassigned margins on local recurrence after NAC in dogs with mast cell tumours (MCTs). METHODS: A retrospective analysis was conducted for dogs with MCTs undergoing NAC consisting of vinblastine and prednisolone, subsequent tumour resection and lymphadenectomy, and a minimum follow-up of 6 months. Surgical margins were reassigned based on the size of the MCT after NAC. Pre- and post-NAC measurements of MCTs were recorded. The margin status was assessed with a combined radial and tangential sectioning technique; pre-NAC MCT cytograde and lymph node (LN) cytological status were compared with the Kiupel grade and Weishaar stage, respectively. RESULTS: Twenty-two dogs were included. MCT shrinkage after NAC consistently occurred, with a median reduction rate of 40.4% (range 5%-94.5%). Margins were complete in 15 of 22 dogs, and two MCTs and three LNs appeared histologically downgraded and downstaged, respectively. Two (9.1%) MCTs recurred. LIMITATIONS: The limitations of this study were the small sample size and relatively short follow-up. CONCLUSION: NAC leads to shrinkage of canine MCTs, with the resulting reassigned surgical margins being associated with a low recurrence rate.
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Doenças do Cão , Margens de Excisão , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Animais , Cães , Doenças do Cão/tratamento farmacológico , Doenças do Cão/cirurgia , Doenças do Cão/patologia , Recidiva Local de Neoplasia/veterinária , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos , Terapia Neoadjuvante/veterinária , Masculino , Feminino , Resultado do Tratamento , Quimioterapia Adjuvante/veterináriaRESUMO
A 2-year-old female Bengal cat was referred for acute right forelimb lameness one month after ovariectomy. Physical examination revealed multifocal pain on bone palpation and fever. Radiographs showed mixed lytic-proliferative polyostotic diaphyseal osteopathy of multiple bone segments. Histopathologic evaluation of bone biopsies showed severe chronic pyogranulomatous osteomyelitis and multidrug-resistant Serratia marcescens was cultured. Antibiotic therapy with piperacillin-tazobactam was administered for 60 days, based on susceptibility testing. Lameness and bone pain resolved within 15 days, and radiographs after 30 days showed decreased bone lysis. At a 6-month recheck, the cat recovered completely, and only bone remodelling was evident on radiographs. Multifocal bacterial haematogenous osteomyelitis (HO) caused by Serratia marcescens was diagnosed in an adult immunocompetent cat. HO is infrequently reported in dogs and cats with young and immunocompromised patients being most at risk. Prior ovariectomy and anaesthesia may have predisposed the cat to the development of a hospital-associated infection (HAI), as other aetiologies or predisposing causes for osteomyelitis were reasonably excluded. Serratia marcescens is a gram-negative bacterium recently reported as responsible for human and veterinary HAIs, although it has never been stated for HO in small animals. Early recognition and antibiotic therapy led to good outcome in this case.
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Osteosarcoma is the most common malignant primary bone cancer, but it is infrequently reported in cats. Feline appendicular osteosarcoma typically exhibits good prognosis when treated with surgery alone. A retrospective multi-institutional study was conducted to identify possible prognostic factors. Cats diagnosed with appendicular osteosarcoma were included if initial staging and follow-up information were available. Data including signalment, tumour characteristics, treatment modalities, and survival outcomes were collected and analysed. Fifty-six cats were included; the femur was the most frequently affected bone. Eight cats had distant metastasis at admission and an additional 9 developed metastatic disease during follow-up, resulting in an overall metastatic rate of 30%. Forty-nine (87.5%) cats underwent surgery, and 4 also received adjuvant chemotherapy. Among operated cats, median time to local progression (TTLP), time to distant progression and tumour-specific survival (TSS) were not reached. One- and 2-year survival rates were 66% and 55%, respectively. Seven (12.5%) cats received no treatment; 1- and 2-year survival rates were 25% and 0%, respectively. Operated cats had significantly longer TTLP (P < .001) and TSS (P = .001) compared with non-operated cats. Among operated cats, young age negatively impacted local tumour progression, while the presence of distant metastasis at diagnosis was associated with a higher risk of tumour-related death. This study reaffirms the good prognosis for cats with appendicular osteosarcoma undergoing surgery, but sheds light on some additional factors to consider. Accurate initial staging is recommended, as the metastatic rate may exceed many previous estimations. Surgery substantially extends survival time, whereas the role of chemotherapy remains uncertain.
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Doenças do Gato , Osteossarcoma , Animais , Osteossarcoma/veterinária , Osteossarcoma/terapia , Osteossarcoma/patologia , Gatos , Doenças do Gato/patologia , Estudos Retrospectivos , Masculino , Feminino , Neoplasias Ósseas/veterinária , Neoplasias Ósseas/patologia , Neoplasias do Apêndice/veterinária , Neoplasias do Apêndice/patologia , ItáliaRESUMO
Background: Hand-sewn intestinal resection and anastomosis are commonly performed in veterinary medicine. The outcome of the hand-sewn side-to-side anastomosis (SSA) technique has never been described and compared to other techniques in dogs and cats. Aim: The study aims to describe the side-to-side hand-sewn anastomosis technique in small animals and to compare it with the end-to-end technique. Methods: A retrospective evaluation of the clinical records of dogs and cats that underwent enterectomy between 2000 and 2020 and were treated with side-to-side or end-to-end anastomosis (EEA) was performed. Results: Of the 52 dogs and 16 cats included in the study, 19 dogs and 6 cats received an SSA, and the remaining received an EEA. No intraoperative complication was reported. However, short-term complication rates were comparable, and mortality rates in the EEA group were higher. At the same time, stenosis was a frequent complication of SSA and was never reported following EEA. Conclusion: End-to-end technique remains the gold standard for hand-sewn intestinal anastomosis in small animals. However, SSA can be considered for selected cases with acceptable morbidity and mortality rates.
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Anastomose Cirúrgica , Doenças do Gato , Doenças do Cão , Animais , Gatos/cirurgia , Cães , Anastomose Cirúrgica/métodos , Anastomose Cirúrgica/normas , Anastomose Cirúrgica/veterinária , Doenças do Gato/cirurgia , Doenças do Cão/cirurgia , Estudos Retrospectivos , Técnicas de Sutura/normas , Técnicas de Sutura/veterináriaRESUMO
Background: Duodenal ulceration (DU) in dogs derives from different causes but has never previously been related to gallbladder agenesis (GA). GA is a rare congenital disorder in dogs and is considered a predisposing factor for DU in humans. Case Description: A 5-month-old intact female Maltese was presented for acute vomiting and diarrhea. Abdominal ultrasound suggested duodenal perforation and absence of the gallbladder. Exploratory laparotomy was performed to treat the perforation and confirmed GA. Hepatic ductal plate malformation (DPM) was histologically diagnosed in liver biopsy, but no signs of liver dysfunction were detected by blood work at first admission. Two months later, the dog developed signs of portal hypertension and medical treatment was started. However, the clinical condition gradually worsened until liver failure and the dog was euthanized 8 months after surgery. Necropsy confirmed hepatic abnormalities. Conclusion: This report describes a case of DU associated with GA and DPM in a dog. As in humans, GA may represent a hepatobiliary disease predisposing to gastroduodenal ulcerations.
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Úlcera Duodenal , Hipertensão Portal , Humanos , Cães , Feminino , Animais , Vesícula Biliar/anormalidades , Vesícula Biliar/patologia , Úlcera Duodenal/complicações , Úlcera Duodenal/diagnóstico , Úlcera Duodenal/veterinária , Hipertensão Portal/veterináriaRESUMO
Surgery-induced stress and anesthesia-related immunosuppression are believed to play a critical role in human oncology patients. Studies have hypothesized that anesthesia influences patients' outcome, promoting tumor recurrence and metastasis. Aim of the study was to investigate whether anesthesia promoted relapse in dogs with diffuse large B-cell lymphoma (DLBCL). Medical records were searched for dogs with DLBCL, that were in complete remission (CR) after the same chemo-immunotherapy protocol. Dogs receiving anesthesia were included if the procedure was performed while in CR. Time to relapse (TTR) was obtained via Kaplan-Meier method. Association between anesthesia and relapse was assessed using a nested case-control design and estimated using conditional logistic regression. Sixty-one dogs with DLBCL were included. Overall median TTR was 329 days (95% CI, 281-377). Forty-eight (79%) dogs relapsed during the study period, while 13 (21%) were still in CR at data analysis closure. Eighteen (30%) dogs received anesthesia with opioids, propofol, and isoflurane or sevoflurane. The relative risk of lymphoma relapse for dogs undergoing anesthesia was significantly higher compared with dogs not undergoing anesthesia, with an odds ratio of 3.09 (P = 0.019) on multivariable analysis. Anesthesia may promote relapse in dogs with DLBCL treated with chemo-immunotherapy, although a role of perioperative stress cannot be ultimately excluded. Considering the high frequency of anesthetic procedures required for diagnostic and therapeutic protocols among oncology patients, it is of utmost interest to characterize the effects of single anesthetic agents on the immune system. Further prospective studies are needed to better define the impact of anesthesia on patients' outcome.
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The industrialization of perovskite solar cells relies on solving intrinsic-to-material issues. To reach record efficiencies perovskite deposition needs to be finely adjusted by multi-step processes, in a humidity free glove-box environment and by means of hardly scalable techniques often associated with toxic solvents and anti-solvent dripping/bath. Herein, the use of polymeric material is proposed to deposit perovskite layers with easy processability. To the scope, a starch-polymer/perovskite composite is developed to suit slot-die coating technique requirement, allowing the deposition of hybrid halide perovskite material in a single straightforward step without the use of toxic solvents, and in uncontrolled humid environment (RH up to 70 %). The starch-polymer increases the viscosity of the perovskite precursor solutions and delays the perovskite crystallization that results in the formation of perovskite films at mild temperature (60 °C) with good morphology. These innovative inks enables the fabrication of flexible solar cells with p-i-n configuration featured by a power conversion efficiency higher than 3 %. . Overall, this approach can be exploited in the future to massively reduce perovskite manufacturing costs related to keeping the entire fabrication line at high-temperature and under nitrogen or dry conditions.
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A deepened investigation on an innovative organic-inorganic hybrid material, referred to as ECS-14 (where ECS = Eni carbon silicates), revealed the possibility to use them as gas sensors. Indeed, among ECS phases, the crystalline state and the hexagonal microplateletlike morphology characteristic of ECS-14 seemed favorable properties to obtain continuous and uniform films. ECS-14 phase was used as functional material in screen-printable compositions and was thus deposited by drop coating for morphological, structural, thermal, and electrical characterizations. Possible operation at room temperature was investigated as technological progress, offering intrinsic safety in sensors working in harsh or industrial environments and avoiding high power consumption of most common sensors based on metal oxide semiconductors. Electrical characterization of the sensors based on ECS-14 versus concentrations of gaseous analytes gave significant results at room temperature in the presence of humidity, thereby demonstrating fundamental properties for a good quality sensor (speed, reversibility, and selectivity) that make them competitive with respect to systems currently in use. Remarkably, we observed functionality reversal of the organic and inorganic components; that is, in contrast to other hybrids, for ECS-14 the functional site has been ascribed to the inorganic phase while the organic component provided structural stability to the material. The sensing mechanism for humidity was also investigated.
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Due to their optical, photo-luminescence (PL), and afterglow properties, barium titanosilicates are compounds of great interest for functional materials and light-emitting devices. Among them, BaTiSi2O7 (BTS2) is certainly one of the most intriguing; it displays peculiar properties (e.g. PL orange emission) whose exhaustive explanation has been hampered to date by the lack of a structure model. In this work, BTS2 and the related compound BaTiSi4O11 (BTS4) were synthesized through conventional solid-state reaction methods. BTS2 invariably shows complex twinning patterns. Thus, its structure solution and Rietveld structure refinement were attempted using synchrotron powder diffraction. BTS2 was found to be an intergrowth of monoclinic and triclinic crystals. The monoclinic phase has the space group P21/n and unit cell a = 7.9836â (3), b = 10.0084â (4), c = 7.4795â (3)â Å, and ß = 100.321â (3)°, whereas the triclinic phase has the space group P\bar 1 and unit cell a = 7.99385â (4), b = 10.01017â (5), c = 7.47514â (3)â Å, α = 90.084â (8), ß = 100.368â (8) and γ = 89.937â (9)°. These lattices can be seen as a distortion of that of tetragonal synthetic ß-BaVSi2O7 with Ti in place of V. The structure models obtained from this study confirm the presence of fivefold coordinated Ti atoms in a distorted pyramidal configuration. The proposed solution supports existing theories for the explanation of the PL orange colour in BTS2.
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The influence of H3BO3 on the crystallization of hybrid organic-inorganic aluminosilicates denoted as Eni Carbon Silicates (ECS's) was investigated. Syntheses were carried out at 100 °C under different experimental conditions, using bridged silsesquioxanes of general formula (EtO)3Si-R-Si(OEt)3 (R = -C6H4- (BTEB), -C10H6- (BTEN) and -C6H4-C6H4- (BTEBP)), in the presence of equimolar concentrations of NaAlO2 and H3BO3. The study, involving the synthesis of three different but structurally related phases (ECS-14 from BTEB, ECS-13 here described for the first time from BTEN, and ECS-5 from BTEBP), confirmed a catalytic role for H3BO3 which in general increased the crystallization rate and improved the product quality in terms of amount of crystallized phase (crystallinity), size of the crystallites and phase purity, while it was weakly incorporated in trace amounts in the framework of ECS's.
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The first solvent-free crystal structure of PCBM, an organic semiconductor widely used in solvent-free nanocrystalline films in plastic solar cells, is reported and its relevance to structure-property relationships discussed. The PCBM structure, obtained from o-dichlorobenzene solvates by solvent abstraction, was solved using powder diffraction, demonstrating this possibility for functionalized fullerenes.
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Fontes de Energia Elétrica , Fulerenos/química , Simulação de Dinâmica Molecular , Nanoestruturas/química , Energia Solar , Modelos Moleculares , Estrutura MolecularRESUMO
ECS-14, a crystalline microporous hybrid organic-inorganic aluminosilicate, has been synthesized by using 1,4-bis-(triethoxysilyl)-benzene (BTEB) as a source of silica. Its structure contains a system of linear channels with 12-membered ring openings, running along the [001] direction, resembling the pore architecture of the AFI framework type.
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Combinatorial screening using precipitation methods at room temperature can lead to a great diversity of carboxylate based Metal Organic Frameworks (MOFs) including already known or original porous solids. The investigation of the synthesis of MOFs in different solvent and solvent mixtures includes the use of solvents such as alcohols and tetrahydrofuran (THF) which would greatly facilitate large scale production. We also show the application of Principal Component Analysis (PCA) and clustering techniques on large libraries of XRD diffraction files in order to identify classes of similar phases and peculiar phases. The combinatorial screening of 105 samples in the La/btc system has led to the identification of two phases which are solvent depending. On the La(btc) compound, the CO2 adsorption measurements reveal a guest-host interactions as supported by XRD phase transformation upon thermal treatment. The mass transport can be assigned to a "single file diffusion" regime due to the one dimensional channel porous structure associated to small pore size.