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1.
J Equine Vet Sci ; 136: 105069, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599258

RESUMO

The aim of this study was to evaluate two cryoprotectants, dimethylformamide (DMF) and methylformamide (MF) in two concentrations (5 and 7 %) in vitro in donkey semen using a rapid freezing technique and the effect on pregnancy rates in mares. Twenty-four ejaculates from 8 jacks (n = 8; r = 3) were divided into 4 extenders: BotuSemen Gold with 5 % or 7 % MF and 5 % or 7 % DMF, all containing 11 % lactose, 20 % egg-yolk and 0.5 % Equex. Post-thaw evaluations included: sperm motility, membrane function and acrosome status. A linear mixed effect model was used to test the effect of different freezing media on semen parameters. No differences were observed between the 4 freezing media used, for any of the seminal parameters (P > 0.05). However, samples with 5 % DMF showed the highest percentages of sperm with acrosomes and functional membranes (DMF: 5 %: 53.67 ± 22.01; 7 %: 33.92 ± 23.4; MF: 5 %: 44.5 ± 20.46; 7 %: 38.75 ± 27.4) (Data: mean ± SD; P > 0.05). Hence, thirty mares were inseminated: 15 with 5 % DMF and 15 with 7 % DMF. The pregnancy rate was 46 % (7/15) and 0 % (0/15) using the extender with 5 % or 7 % DMF, respectively (P = 0.003). To conclude, the use of 5 % or 7 % of MF or DMF did not affect the in vitro parameters. Despite the lack of differences in vitro with the two DMF concentrations, in vivo results only showed pregnancies when using 5 % DMF. Thus, the results of this study demonstrate the importance of accompanying in vitro semen evaluations with studies that evaluate post-insemination pregnancy rates.


Assuntos
Criopreservação , Crioprotetores , Equidae , Preservação do Sêmen , Animais , Equidae/fisiologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Crioprotetores/farmacologia , Feminino , Masculino , Criopreservação/métodos , Criopreservação/veterinária , Gravidez , Dimetilformamida/farmacologia , Inseminação Artificial/veterinária , Sêmen/efeitos dos fármacos , Sêmen/química , Motilidade dos Espermatozoides/efeitos dos fármacos , Formamidas
2.
Vet Res Commun ; 48(2): 1253-1256, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38105361

RESUMO

In the last years, there has been an increasing interest in llamas, not only as part of a productive system, but mostly as companion animals. Most reports regarding clinical biochemistry and haematology include few llamas and details about their health status are not available. The present study aims to provide haematological and biochemical parameters for llamas of known health status. Twenty-three non-pregnant females and seven males that live in Buenos Aires, Argentina (34°36'S, 58°22'W, at sea level) were studied. Llamas were clinically healthy, in good nutritional status. Animals were kept at grass and were fed hay bale or pellets and water ad libitum. Blood samples were collected by jugular venipuncture in spring. Packed cell volume, leucocyte count, differential white cell count, platelets count, urea, creatinine, total proteins, albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, glucose, calcium and phosphate were assessed. No significant differences were observed between males and females, except for platelet count and calcium, which was greater in males (P˂0.01). Values obtained for the different parameters were similar to those previously reported, except for monocytes, alkaline phosphatase, glucose and calcium, that were lower and lymphocytes and platelets count, that were higher in this study. In conclusion, different ambient and methodological conditions might affect some parameters. The parameters hereby presented are representative of llama's population living at sea level in South America.


Assuntos
Camelídeos Americanos , Hematologia , Masculino , Feminino , Animais , Cálcio , Fosfatase Alcalina , Glucose , Nível de Saúde , Valores de Referência , Análise Química do Sangue/veterinária
3.
Sci Data ; 10(1): 427, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400466

RESUMO

Systematic and timely documentation of triggered (i.e. event) landslides is fundamental to build extensive datasets worldwide that may help define and/or validate trends in response to climate change. More in general, preparation of landslide inventories is a crucial activity since it provides the basic data for any subsequent analysis. In this work we present an event landslide inventory map (E-LIM) that was prepared through a systematic reconnaissance field survey in about 1 month after an extreme rainfall event hit an area of about 5000 km2 in the Marche-Umbria regions (central Italy). The inventory reports evidence of 1687 triggered landslides in an area of ~550 km2. All slope failures were classified according to type of movement and involved material, and documented with field pictures, wherever possible. The database of the inventory described in this paper as well as the collection of selected field pictures associated with each feature is publicly available at figshare.

4.
Environ Res ; 207: 112112, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34600880

RESUMO

Graphitic carbon nitride (g-C3N4) is an emerging metal-free photocatalyst, however, engineering the photocatalytic efficiency for the effective degradation of hazardous molecules is still challenging. An unstable and low bandgap CuWO4 was composited with g-C3N4 to achieve synergistic benefits of tuning the visible light responsiveness and stability of CuWO4. CuWO4/g-C3N4 nanocomposite exhibited a relatively high visible light absorption region and the bandgap was modified from 2.77 to 2.53 eV evidenced via UV-DRS. Moreover, the fast electron transfer rate was observed with CuWO4/g-C3N4 nanocomposite as confirmed using PL and photocurrent studies. XRD, FT-IR, and HR-TEM analyses signified the formation of CuWO4/g-C3N4 nanocomposite. CuWO4/g-C3N4 nanocomposite showed enhanced photocatalytic degradation of Tetracycline (TC) about ∼7.4 fold greater than pristine g-C3N4 in 120 min. Notably, the OH• and •O2- radicals played a most significant role in photocatalytic TC degradation. Furthermore, the energy band structure, density of state, and Bader charge analyses of these molecules were performed.


Assuntos
Nanocompostos , Tetraciclina , Antibacterianos/química , Catálise , Luz , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Lasers Med Sci ; 37(3): 1635-1641, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34580789

RESUMO

The purpose of this study is to evaluate the efficiency of CO2 laser colposcopic guided surgery performed in an outpatient see and treat setting in the management of VHSIL. Women with a suspected diagnosis of VHSIL and no vulvoscopic suspicion of vSCC were enrolled. An electronic register of CO2 laser treatment was created where description of performing parameters (excision or ablation) was specified and personal history was recorded. Statistical analysis was performed by Fisher's exact test. Relative risks (RR) of risk factor were calculated and expressed in odds. From September 2014 to September 2018, we enrolled a total of 63 patients who underwent CO2 laser procedure and had a minimum follow-up time of 2 years at Careggi University Hospital in Florence. Forty-eight (76.2%) patients underwent laser excision and 15 (23.8%) patients underwent ablative treatment without histological results. Undertreatment was performed in 3 cases (6.3%) with definitive histology of vSCC. Therapeutical appropriateness of CO2 laser excision was reached in 85.4% of the cases (41/48). No volunteer loss to follow-up was registered; thus, fidelity to treatment was assess at 100%. Recurrence rate within 2 years attested in 8/60 followed patients (13.3%). No personal factor was found to influence the VHSIL course. CO2 laser excision may represent an excellent therapeutic option to VHSIL because it provides adequate oncological purpose with good cosmetic and functional results and high patients' loyalty to treatment. An expert team could allow to undergo patients with VHSIL suspicion to unique diagnostic and therapeutic procedure with significant benefits.


Assuntos
Terapia a Laser , Lasers de Gás , Neoplasias do Colo do Útero , Neoplasias Vulvares , Colposcopia , Feminino , Humanos , Lasers de Gás/uso terapêutico , Gravidez , Fatores de Risco , Neoplasias do Colo do Útero/diagnóstico , Neoplasias Vulvares/diagnóstico , Neoplasias Vulvares/patologia , Neoplasias Vulvares/cirurgia
6.
Sci Rep ; 11(1): 24313, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34934129

RESUMO

A new concept of oxide-metal-oxide structures that combine photothermoelectric effect with high reflectance (~ 80%) at wavelengths in the infrared (> 1100 nm) and high transmittance in the visible range is reported here. This was observed in optimized ITO/Ag/ITO structure, 20 nm of Silver (Ag) and 40 nm of Indium Tin Oxide (ITO), deposited on Aluminum doped Zinc Oxide (AZO) thin film. These layers show high energy saving efficiency by keeping the temperature constant inside a glazed compartment under solar radiation, but additionally they also show a photothermoelectric effect. Under uniform heating of the sample a thermoelectric effect is observed (S = 40 mV/K), but when irradiated, a potential proportional to the intensity of the radiation is also observed. Therefore, in addition to thermal control in windows, these low emission coatings can be applied as transparent photothermoelectric devices.

7.
Vet World ; 13(8): 1627-1634, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33061237

RESUMO

BACKGROUND AND AIM: Mast cell tumors (MCTs) are malignant neoplasms that are common in dogs. Their biological behavior is variable and unpredictable. The aim of the present study was to analyze the histological classification and expression of markers of canine MCTs. MATERIALS AND METHODS: Thirty samples of canine MCTs were graded according to the histological classification methods of Patnaik and those of Kiupel. The expression of phosphoprotein 53 (p53) and c-kit proteins was quantified by immunohistochemistry using image processing software, ImageJ - a public domain computer program, developed at the National Institutes of Health. RESULTS: It was possible to determine the grade of 100% of the samples. According to Patnaik's classification, 20.00% of the samples were Grade 1, 43.30% were Grade 2, and 36.70% were Grade 3. According to Kiupel's classification, 56.67% of the samples were of high intensity and 43.33% were of low intensity. Grade 1 tumors had the highest expression of p53 and c-kit, and Grade 2 had the lowest expression. The results showed that it is necessary to perform both histological grading methods. The classification into high and low intensity may provide more consistent results than the three-level grading system. However, a smaller number of categories, although it facilitates the classification, may not be sufficient for the prognosis. CONCLUSION: Quantitative evaluation of p-53 and c-kit expression is a useful tool to increase the accuracy of the analysis and to aid in choosing the treatment method for canine MCTs. Histological grading should be combined with other diagnostic methods.

8.
J Comp Pathol ; 179: 36-40, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32958145

RESUMO

The aims of this study were to investigate the potential association of arginine vasopressin type 2 receptor (AVPR2) in canine mammary tumours with expression of oestrogen receptors α (ORα) and ß (ORß) and clinicopathological features of the neoplasms. Twenty-six canine mammary tumour samples (11 benign, 15 malignant) were immunolabelled for AVPR2, ORα and ORß antigens. Moderate to intense immunolabelling of AVPR2 antigen, found in all neoplasms, was not significantly associated with expression of ORα or ORß antigens or with clinicopathological features. These findings indicate a potential role for AVPR2 in the development of canine mammary tumours and the use of AVPR2-selective vasopressin analogues as therapeutic options.


Assuntos
Doenças do Cão/metabolismo , Doenças do Cão/patologia , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Receptores de Vasopressinas/biossíntese , Animais , Biomarcadores Tumorais/metabolismo , Cães , Feminino
9.
Sci Total Environ ; 748: 141373, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32805568

RESUMO

Extreme environmental events can strongly affect coastal marine ecosystems but are typically unpredictable. Reliable data on benthic community conditions before such events are rarely available, making it difficult to measure their effects. At the end of October 2018, a severe storm hit the Ligurian coast (NW Mediterranean) producing damages to coastal infrastructures. Thanks to recent data collected just before the event on two Posidonia oceanica seagrass meadows hit by the storm, it has been possible to assess the impact of the event on one of the most valuable habitats of the Mediterranean Sea. By means of seagrass cover and depth data gathered along four depth transects positioned within the two meadows in areas differently exposed to the storm waves, and by using models (WW3® + SWAN + XBeach 1D) to evaluate wave height and bed shear stress, we showed that meadows experienced erosion and burial phenomena according to exposure. Paradoxically, meadows in good conditions suffered more damage as compared to those already suffering from previous local anthropogenic impacts. Besides the direct effect of waves in terms of plant uprooting, a major loss of P. oceanica was due to sediment burial in the deepest parts of the meadows. Overall, the loss of living P. oceanica cover amounted to about 50%. Considering that previous research showed that the loss of the original surface of P. oceanica meadows in 160 years due to anthropogenic pressures was similarly around 50%, the present study documented that an extreme environmental event can generate in a single day a loss of natural capital equal to that produced gradually by more than a century of human impact.


Assuntos
Alismatales , Ecossistema , Pradaria , Humanos , Mar Mediterrâneo
10.
Diabetes Res Clin Pract ; 166: 108309, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32650034

RESUMO

AIMS: This study evaluates the adherence to postpartum type 2 diabetes mellitus (T2DM) screening in women with previous gestational diabetes (GDM) and identifies elements associated with poor attendance. METHODS: We retrospectively collected data from 650 consecutive women with GDM between 2016 and 2018, who should had 75 g-OGTT, 4-12 weeks after delivery. Impaired glucose regulation (IGR) was defined according with ADA criteria. RESULTS: Only 41% of women had postpartum OGTT. Of these, 1.9% received T2DM diagnosis, with IGR prevalence of 18%. After introducing a recommendation letter, adherence to screening increased (47% in 2017 and 43% in 2018 vs. 32% in 2016). Screening procedure was less common in women with: no-family history of T2DM (38% vs. 46%; p < 0.05), age <35 (33% vs. 47%; p < 0.01), lower level of education (32% no-high-school-diploma vs. 35% high-school-diploma vs. 49% university-degree; p < 0.01) and unstable employment (35% vs. 44%; p < 0.05). At multivariate logistic regression analysis, age <35 years (OR 1.61; 95%CI: 1.14-2.28) and lowest educational level (OR 1.64; 95% CI: 1.13-2.37, compared to University degree) were independently associated with non-adherence. CONCLUSION: Only 41% of women had postpartum T2DM screening. Women with lower attendance are those with age <35 years or low educational level. Further strategies are needed to implement postpartum test.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Período Pós-Parto/fisiologia , Adulto , Feminino , Humanos , Gravidez , Estudos Retrospectivos
11.
Artigo em Inglês | MEDLINE | ID: mdl-31815087

RESUMO

In this work, eco-friendly magnesium-silicide (Mg2Si) semiconducting (n-type) thermoelectric pastes for building components concerning energy-harvesting devices through 3D printing, spray and electrospinning were synthetized and tested for the first time. The Mg2Si fine powders were obtained through the combination of ball milling and thermal annealing under Ar atmosphere. While the latter process was crucial for obtaining the desired Mg2Si phase, the ball milling was indispensable for homogenizing and reducing the grain size of the powders. The synthetized Mg2Si powders exhibited a large Seebeck coefficient of ~ 487 µV/K and were blended with a polymeric solution in different mass ratios to adjust the paste viscosity to the different requirements of 3D printing, electrospinning and low-pressure spray. The materials produced in every single stage of the paste synthesis were characterized by a variety of techniques that unequivocally prove their viability for producing thermoelectric parts and components. These can certainly trigger further research and development in green thermoelectric generators (TEGs) capable of adopting any form or shape with enhanced thermoelectric properties. These green TEGs are meant to compete with common toxic materials such as Bi2Te3, PbTe and CoSb that have Seebeck coefficients in the range of ~ 290-700 µV/K, similar to that of the produced Mg2Si powders and lower than that of 3D printed bulk Mg2Si pieces, measured to be ~ 4866 µV/K. Also, their measured thermal conductivities proved to be significantly lower (~ 0.2 W/mK) than that reported for Mg2Si (≥ 4 W/mK). However, it is herein demonstrated that such thermoelectric properties are not stable over time. Pressureless sintering proved to be indispensable, but difficultly achievable by long thermal annealing (even above 32 h) in inert atmosphere at 400 °C, at least for bulk Mg2Si pieces constituted by a mean grain size of 2-3 µm. Hence, for overcoming this sintering challenge and become the silicide's extrusion viable in the production of bulk thermoelectric parts, alternative pressureless sintering methods will have to be further explored.

12.
Anim Reprod Sci ; 208: 106105, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405457

RESUMO

South American camelids (SAC) are induced ovulating animals. In unmated females, ovarian follicle development occurs in waves of growth and regression, while mating when there is the presence of a mature follicle leads to ovulation. The capacity to respond to an ovulatory stimulus depends on the stage of the follicular wave development. Treatments to control ovarian follicular development have been performed to synchronize timing of wave emergence and development of the dominant follicle at a predictable time. Thus, synchronization of the time of follicular wave development allows for performing fixed time mating or artificial insemination, and superestimulatory treatments for multiple follicule development. Protocols are based on removal of the suppressive effect of the dominant follicle, that can be achieved by physical ablation or by inducing ovulation (with LH or GnRH) or atresia (with progesterone or progestagens alone or combined with estradiol) of this follicle. Differences between treatments should be taken into consideration when choosing a protocol for fixed time mating or artificial insemination, especially when applying the use these technologies for SAC production by commercial enterprises. Furthermore, the objective of applying synchronization protocols should be considered, because not all of these are effective in inhibiting follicular growth before initiation of a superestimulatory treatment for multiple follicle development.


Assuntos
Camelídeos Americanos/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Sincronização do Estro/métodos , Feminino , Inseminação Artificial , Indução da Ovulação
13.
J Comp Pathol ; 170: 26-33, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31375156

RESUMO

The aims of the present study were: (1) to investigate the presence of oxytocin receptors in benign and malignant canine mammary tumours (CMTs) and to evaluate the possible association between oxytocin receptor (OTR) expression and the expression of oestrogen receptor (OR) α and ORß, and (2) to examine associations between receptor expression and tumour size, clinical stage, histological subtype, tumour grading and lymph node status. Forty-three canine mammary tumour samples (19 benign, 24 malignant) were examined by immunohistochemistry to detect OTR, ORα and ORß expression. Results were expressed as total score for each receptor, calculated as the sum of the percentage of positive cells and the intensity of immunolabelling. In all of the evaluated mammary tumour samples, OTRs were identified and their expression tended to be higher in benign tumours than malignant tumours. Among the malignant tumours, the expression of OTR was significantly higher in grade I and II lesions than in grade III lesions. ORα-positive tumours had a tendency towards a higher OTR total score than ORα-negative tumours. These results report for the first time that CMTs express OTRs and their expression is associated with the presence of ORα. An interaction between oxytocin and the OTR might play a role in the development and progression of this type of neoplasia.


Assuntos
Doenças do Cão/metabolismo , Doenças do Cão/patologia , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Receptores de Ocitocina/biossíntese , Animais , Biomarcadores Tumorais/análise , Cães , Receptor alfa de Estrogênio/biossíntese , Feminino
15.
Nutr Metab Cardiovasc Dis ; 29(6): 598-603, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30954416

RESUMO

BACKGROUND AND AIMS: Screening for Gestational Diabetes (GDM) is usually recommended between 24 and 28 weeks of pregnancy; however available evidence suggests that GDM may be already present before recommended time for screening, in particular among high-risk women as those with prior GDM or obesity. The purpose of this retrospective study was to evaluate whether early screening (16-18 weeks) and treatment of GDM may improve maternal and fetal outcomes. METHODS AND RESULTS: In 290 women at high-risk for GDM, we analyzed maternal and fetal outcomes, according to early or standard screening and GDM diagnosis time. Early screening was performed by 50% of high-risk women. The prevalence of GDM was 62%. Among those who underwent early screened, GDM was diagnosed at the first evaluation in 42.7%. Women with early diagnosis were more frequently treated with insulin and had a slightly lower HbA1c than women with who were diagnosed late. No differences were observed in the prevalence of Cesarean section, operative delivery, gestational age at the delivery, macrosomia, neonatal weight, Ponderal Index and Large-for-Gestational-Age among women with early or late GDM diagnosis or NGT. However, compared to NGT women, GDM women, irrespective of the time of diagnosis, had a lower gestational weight gain, lower prevalence of macrosomia (3.9% vs. 11.4%), small (1.7% vs. 8.3%) as well as large for gestational age (3.3% vs. 16.7%), but higher prevalence of pre-term delivery (8.9% vs. 2.7%). CONCLUSION: Early vs. standard screening and treatment of GDM in high-risk women is associated with similar short-term maternal-fetal outcomes, although women with an early diagnosis were treated to a greater extent with insulin therapy.


Assuntos
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/tratamento farmacológico , Intervenção Médica Precoce , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Programas de Rastreamento , Cuidado Pré-Natal/métodos , Adulto , Diabetes Gestacional/sangue , Diabetes Gestacional/epidemiologia , Diagnóstico Precoce , Feminino , Humanos , Itália/epidemiologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Gynecol Endocrinol ; 35(9): 737-751, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30990092

RESUMO

Gestational diabetes mellitus (GDM) is a complex condition whose physiopathology to date has not been completely clarified. Two major metabolic disorders, insulin resistance and ß-cells dysfunction, play currently major role in pathogenesis of GDM. These elements are influenced by the amount of adipose tissue present before and/or during the pregnancy. Consequently, adipokines (adiponectin (APN), leptin (LPT), adipocyte fatty acid-binding protein, resistin, visfatin, omentin, vaspin, apelin, chemerin) secreted by adipose tissue, may contribute directly and/or indirectly, through the enhancement of chronic inflammation, aggravating insulin resistance and promoting GDM onset. This review aims to outline the potential physiopathological and prognostic role in GDM of adipokines, mainly APN and LPT.


Assuntos
Adipocinas/fisiologia , Diabetes Gestacional/etiologia , Tecido Adiposo/metabolismo , Animais , Diabetes Gestacional/metabolismo , Feminino , Humanos , Resistência à Insulina/fisiologia , Gravidez
17.
Ultrason Sonochem ; 54: 302-310, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30712858

RESUMO

Pollutants of emerging concern contaminate surface and ground water. Advanced oxidation processes treat these molecules and degrade them into smaller compounds or mineralization products. However, little information on coupled advanced oxidation techniques and on the degradation pathways of these pollutants is available to identify possible ecotoxic subproducts. In the present work, we investigate the ultrasound assisted photocatalytic degradation pathway of the herbicide Isoproturon. We worked in batch mode in a thermostatic glass reactor. We compared the activity of nanometric TiO2 P25 with that of Kronos 1077, a micrometric TiO2. We discuss the individual, additive and synergistic degradation action of photolysis, sonolysis, sonophotolysis, and sonophotocatalysis by varying catalyst loading and/or ultrasound power for the last three techniques. With 0.1 g L-1 catalyst, photocatalysis and sonophotopcatalysis completely degrade Isoproturon within 240 min and 60 min, respectively (>99% conversion). Sonophotocatalysis breaks Isoproturon down into smaller molecules than photocatalysis alone.

18.
RSC Adv ; 9(61): 35384-35391, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-35528061

RESUMO

Simultaneously transparent and flexible conductive materials are in demand to follow the current trend in flexible technology. The search for materials with compliant optoelectronic properties, while simultaneously retaining their electric conductivity at high strain deformation, comprises promising opportunities in modern nanotechnology. Copper iodide (CuI) is not only the most transparent and highly conductive p-type material, but its optimization has contributed to improved ZT values in planar thin-film thermoelectrics. In this work, the readiness of CuI thin films to transparent, flexible technology is evidenced. A maximum ZT value of 0.29 for single CuI thin films of ca. 300 nm in thickness is reported. Values of open-circuit voltage V oc, short circuit current I sc and power output of p-n thermoelectric modules of Gallium-doped zinc oxide (GZO) and CuI thin films deposited on a transparent flexible Kapton® (type CS) substrate are reported, and a prototype of a flexible transparent thermoelectric generator based on 17 p-n modules was constructed. Bending analysis of CuI thin films reveals interesting, distinct results when submitted to compression and tension analysis - a behaviour not seen in conventional semiconducting thin films under equivalent strain conditions. A plausible account for such diversity is also included.

19.
Ultrason Sonochem ; 51: 462-468, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30001881

RESUMO

Sonochemistry is based on acoustic cavitation, which consist in the formation, growth, and implosive collapse of bubbles within a liquid. Collapsing bubbles generate localized hot spots, characterized by temperatures up to 5000 K and pressures up to 1800 atm. These extreme conditions allow producing a variety of nanostructured and amorphous materials, as well as they are advantageous for chemical processes. Ultrasound requires inexpensive equipment and fewer steps than conventional methods. Combining ultrasound and photocatalysis enhances the performance of the processes, reduces reaction time, avoids the use of extreme physical conditions and improves the photocatalytic materials properties increasing their activity. Here, we reported the positive effect of US in synthesizing Me-modified TiO2 (Me = Ag, Cu, Mn) for pollutants degradation in gas-phase; also, we proved the advantageous application of ultrasound for the photocatalytic removal of organic compounds in water. Ultrasound produced more efficient Me-doped TiO2, which showed higher activity in visible light. When combined with photocatalytic water treatment, the organic compounds degradation and mineralization increases.

20.
J Hazard Mater ; 363: 328-334, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30321837

RESUMO

The ingredients of Pharmaceuticals and Personal Care Products (PPCPs) persist in water and conventional treatment plants are not able to remove them efficiently. Sonochemical treatment is insufficient to mineralize organics such as ibuprofen into CO2 and H2O. TiO2 degrades ibuprofen (IBP) under UV light; however, it does not reach a high grade of conversion. Here, we investigated the mineralization of ibuprofen to CO2 by TiO2 UV-C photocatalysis. We replaced nano-sized P25 (the standard catalyst) with a micro-sized commercial sample of TiO2 to preclude the use of nanoparticles which are dangerous for human health and because typical filtration systems are expensive and inefficient. We deposited micro-TiO2 on glass Raschig rings to ensure an easy recovery and reuse of the photocatalyst and we studied its performance both with a batch and a continuous reactor. Micro-TiO2 mineralized 100% of IBP in 24 h. TiO2-coated glass Raschig rings degraded 87% of IBP in 6 h of UV-C irradiation in a continuous reactor, with a mineralization of 25%. Electronspray ionization mass spectrometer (ESI-MS, positive mode) analyses identified 13 different byproducts and we hypothised a degradration pathway for IBP degradation.


Assuntos
Ibuprofeno/efeitos da radiação , Fotólise , Titânio/química , Poluentes Químicos da Água/efeitos da radiação , Vidro , Ibuprofeno/química , Raios Ultravioleta , Poluentes Químicos da Água/química
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