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1.
Sci Rep ; 14(1): 15649, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977748

RESUMO

In order to enhance the hyperspectral camouflage efficacy of stealth coatings against a natural vegetative backdrop, LiCl, known for its significant hygroscopic properties, was incorporated into green Mg-Al layered double hydroxide (Mg-Al LDHs) material. Micron-sized composite microspheres were subsequently synthesized via the spray-drying granulation technique. The structure, morphology, and chemical composition of these microspheres were thoroughly characterized by X-ray diffraction, scanning electron microscopy, laser particle size analysis, nitrogen adsorption-desorption isotherms, and Fourier-transform infrared spectroscopy. The effect of LiCl content on the moisture absorption capacity and near-infrared reflectance spectra of the microspheres was systematically evaluated. We found that incorporating an optimal amount of LiCl into the internal pores of the Mg-Al LDHs microspheres did not compromise their smooth surface morphology and uniform particulate distribution. Notably, when the LiCl content was 10%, the maximum saturation moisture uptake ratio of the coating increased to 0.75 g/g. This hygroscopicity significantly enhanced the absorption and scattering of near-infrared radiation by the coating while concurrently improving its ability to modulate the shape and reflectance of both the visible and near-infrared spectral curves. Spectral congruence between the synthetic coating and natural green foliage was quantified at 97.41%. Moreover, this performance was maintained over 10 cycles of programmed drying and re-humidification, and the coating consistently demonstrated stable hygroscopic properties and sustained over 95% spectral congruence. These optimized artificial coatings were found to effectively confuse hyperspectral classification algorithms, thus blending seamlessly into a natural foliage backdrop. This study provides a new method for regulating VIS and NIR spectral (visible-near infrared spectrum) features, which will be critical for applications in advanced hyperspectral camouflage materials.

2.
J Dairy Sci ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876215

RESUMO

Feed efficiency is important for economic profitability of dairy farms; however, recording daily dry matter intakes (DMI) is expensive. Our objective was to investigate the potential use of milk mid-infrared (MIR) spectral data to predict proxy phenotypes for DMI based on different cross-validation schemes. We were specifically interested in comparisons between a model that included only MIR data (Model M1), a model that incorporated different energy sink predictors, such as body weight, body weight change, and milk energy (Model M2), and an extended model that incorporated both energy sinks and MIR data (Model M3). Models M2 and M3 also included various cow level variables (stage of lactation, age at calving, parity) such that any improvement in model performance from M2 to M3, whether through a smaller root mean squared error (RMSE) or a greater squared predictive correlation (R2), could indicate a potential benefit of MIR to predict residual feed intake. The data used in our study originated from a multi-institutional project on the genetics of feed efficiency in US Holsteins. Analyses were conducted on 2 different trait definitions based on different period lengths: averaged across weeks vs. averaged across 28-d. Specifically, there were 19,942 weekly records on 1,812 cows across 46 experiments or cohorts and 3,724 28-d records on 1,700 cows across 43 different cohorts. The cross-validation analyses involved 3 different k-fold schemes. First, a 10-fold cow-independent cross-validation was conducted whereby all records from any one cow were kept together in either training or test sets. Similarly, a 10-fold experiment-independent cross-validation kept entire experiments together whereas a 4-fold herd-independent cross-validation kept entire herds together in either training or test sets. Based on cow-independent cross-validation for both weekly and 28-d DMI, adding MIR predictors to energy sinks (Models M3 vs M2) significantly (P < 10-10) reduced average RMSE to 1.59 kg and increased average R2 to 0.89. However, adding MIR to energy sinks (M3) to predict DMI either within an experiment-independent or herd-independent cross-validation scheme seemed to demonstrate no merit (P > 0.05) compared with an energy sink model (M2) for either R2 or RMSE (respectively, 0.68 and 2.55 kg for M2 in herd-independent scheme). We further noted that with broader cross-validation schemes, i.e., from cow-independent to experiment-independent to herd-independent schemes, the mean and slope bias increased. Given that proxy DMI phenotypes for cows would need to be almost entirely generated in herds having no DMI or training data of their own, herd-independent cross-validation assessments of predictive performance should be emphasized. Hence, more research on predictive algorithms suitable for broader cross-validation schemes and a more earnest effort on calibration of spectrophotometers against each other should be considered.

3.
Foods ; 13(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38928805

RESUMO

Lettuce is a globally important cash crop, valued by consumers for its nutritional content and pleasant taste. However, there is limited research on the changes in the growth indicators of lettuce during its growth period in domestic settings. Quality assessment primarily relies on subjective evaluations, resulting in significant variability. This study focused on hydroponically grown lettuce during the rosette stage and investigated the patterns of changes in the indicators and spectral curves over time. By employing spectral preprocessing and selecting characteristic wavelengths, three models were developed to predict the indicators. The results showed that the optimal model structures were S_G-UVE-PLSR (SSC and vitamin C) and Nor-CARS-PLSR (moisture content). The PLSR models achieved prediction set correlation coefficients of 0.8648, 0.8578, and 0.8047, with residual prediction deviations of 1.9685, 1.9568, and 1.6689, respectively. The optimal models were integrated into a portable device, using real-time analysis software written in Matlab2021a, for the prediction of the physicochemical indicators of lettuce during the rosette stage. The results demonstrated prediction set correlation coefficients of 0.8215, 0.8472, and 0.7671, with root mean square errors of prediction of 0.5348, 1.5813, and 2.3347 for a sample size of 180. The small discrepancies between the predicted and actual values indicate that the developed device can meet the requirements for real-time detection.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 476-484, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38932533

RESUMO

Motor imagery is often used in the fields of sports training and neurorehabilitation for its advantages of being highly targeted, easy to learn, and requiring no special equipment, and has become a major research paradigm in cognitive neuroscience. Transcranial direct current stimulation (tDCS), an emerging neuromodulation technique, modulates cortical excitability, which in turn affects functions such as locomotion. However, it is unclear whether tDCS has a positive effect on motor imagery task states. In this paper, 16 young healthy subjects were included, and the electroencephalogram (EEG) signals and near-infrared spectrum (NIRS) signals of the subjects were collected when they were performing motor imagery tasks before and after receiving tDCS, and the changes in multiscale sample entropy (MSE) and haemoglobin concentration were calculated and analyzed during the different tasks. The results found that MSE of task-related brain regions increased, oxygenated haemoglobin concentration increased, and total haemoglobin concentration rose after tDCS stimulation, indicating that tDCS increased the activation of task-related brain regions and had a positive effect on motor imagery. This study may provide some reference value for the clinical study of tDCS combined with motor imagery.


Assuntos
Encéfalo , Eletroencefalografia , Imaginação , Espectroscopia de Luz Próxima ao Infravermelho , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Encéfalo/fisiologia , Imaginação/fisiologia , Córtex Motor/fisiologia , Hemoglobinas/análise , Hemoglobinas/metabolismo , Adulto Jovem
5.
Foods ; 13(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611322

RESUMO

The chemical composition and nutritional content of garlic are greatly impacted by its production location, leading to distinct flavor profiles and functional properties among garlic varieties from diverse origins. Consequently, these variations determine the preference and acceptance among diverse consumer groups. In this study, purple-skinned garlic samples were collected from five regions in China: Yunnan, Shandong, Henan, Anhui, and Jiangsu Provinces. Mid-infrared spectroscopy and ultraviolet spectroscopy were utilized to analyze the components of garlic cells. Three preprocessing methods, including Multiple Scattering Correction (MSC), Savitzky-Golay Smoothing (SG Smoothing), and Standard Normalized Variate (SNV), were applied to reduce the background noise of spectroscopy data. Following variable feature extraction by Genetic Algorithm (GA), a variety of machine learning algorithms, including XGboost, Support Vector Classification (SVC), Random Forest (RF), and Artificial Neural Network (ANN), were used according to the fusion of spectral data to obtain the best processing results. The results showed that the best-performing model for ultraviolet spectroscopy data was SNV-GA-ANN, with an accuracy of 99.73%. The best-performing model for mid-infrared spectroscopy data was SNV-GA-RF, with an accuracy of 97.34%. After the fusion of ultraviolet and mid-infrared spectroscopy data, the SNV-GA-SVC, SNV-GA-RF, SNV-GA-ANN, and SNV-GA-XGboost models achieved 100% accuracy in both training and test sets. Although there were some differences in the accuracy of the four models under different preprocessing methods, the fusion of ultraviolet and mid-infrared spectroscopy data yielded the best outcomes, with an accuracy of 100%. Overall, the combination of ultraviolet and mid-infrared spectroscopy data fusion and chemometrics established in this study provides a theoretical foundation for identifying the origin of garlic, as well as that of other agricultural products.

6.
Angew Chem Int Ed Engl ; 63(16): e202400952, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372593

RESUMO

Cu-based catalysts have been identified as the most promising candidates for generation of C2+ products in electrochemical CO2 reduction reaction. Defect engineering in catalysts is a widely employed strategy for promoting C-C coupling on Cu. However, comprehensive understanding of defect structure-to-activity relationship has not been obtained. In this study, controllable defects generation is achieved, which leads to a series of Cu-based catalysts with various phase mixing degrees. It is observed that the Faradaic efficiency toward C2+ products increases with the phase mixing degree, reaching 81 % at maximum. In situ infrared absorption spectroscopy reveals that the catalysts with higher phase mixing degree tend to form *CO more easily and possess higher retention of *CO under high overpotential window, thereby promoting C-C coupling. This work sheds new light on the relationship between defects and C-C coupling, and the rational developed of more advanced Cu-base catalysts.

7.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(1): 26-29, 2024 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-38384213

RESUMO

In the past 20 years, near infrared spectrum technology has been widely used in human body monitoring due to its non-invasive and real-time characteristics. Oxygen, as the main metabolic substance of the human body, is consumed the most in brain tissue. In order to prevent complications caused by a decrease in brain tissue oxygen during treatment, the patient's brain tissue blood oxygen saturation needs to be monitored in real time. Currently, most of the clinically used non-invasive cerebral blood oxygen detection equipments use dual wavelengths. Other substances on the detection path will cause errors in the measurement results. Therefore, this article proposes a three-wavelength method based on the basic principle of non-invasive monitoring of cerebral blood oxygen using near-infrared spectrum. The brain tissue oxygen saturation monitoring method of detecting light sources was initially verified through the built system, laying the foundation for subsequent system engineering.


Assuntos
Encéfalo , Oxigênio , Humanos , Encéfalo/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Oximetria , Monitorização Fisiológica
8.
J Mot Behav ; 56(4): 393-406, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38240295

RESUMO

Virtual reality has gained more attention in the physical training field, but few studies focus on the effects of VR on older adults. Based on existing study we suggest that VR-based upper limb training might be more effective for older adults and used functional near inferred spectrum and movement analysis to evaluate the effects of VR-based training on older adults. 20 older and 20 youth adults were recruited to perform VR training by extending their upper limb to reaching the objects, and non-VR training as a contrast. Both age-related and task-related differences were found in cortical activation, showing that the VR training has aroused more cortical activation. The older groups have more intensive movement but perform worse in terms of task completion. Both groups performed better in VR, and the difference in the older group was higher.


Assuntos
Extremidade Superior , Realidade Virtual , Humanos , Extremidade Superior/fisiologia , Masculino , Feminino , Idoso , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Envelhecimento/fisiologia
9.
Nano Lett ; 24(1): 326-330, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38146954

RESUMO

Infrared spectrometers with the ability to resolve the spectral intensity and wavelength simultaneously are widely used in industry and the laboratory. However, their huge volume, high price, and cryogenic operating temperature limit their applications in the rapidly developing field of portable devices. Here, we demonstrate a room-temperature self-powered infrared spectrometer based on a single black phosphorus (BP) heterojunction diode. The nonlinearly gate-tunable photocurrent spectrum involving quantum-confined Franz-Keldysh and Burstein-Moss effects in a single BP/MoS2 diode instead of using space-consuming detector arrays provides a new dimension for resolving the intensity and wavelength information of spectra simultaneously. The active area for spectral sensing is only 1500 µm2, and the photodetection range is from 1.7 to 3.6 µm. Room-temperature operation, micrometer-scale size, and silicon-compatible technology make the BP/MoS2 heterojunction a promising configuration for portable spectrometer applications.

10.
Food Chem X ; 19: 100851, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780255

RESUMO

The early symptoms of cork spot disorder in 'Akizuki' pear (Pyrus pyrifolia Nakai) are challenging to distinguish from those in healthy fruits, hindering early identification in production. In this study, samples of cork-browned 'Akizuki' pears, asymptomatic fruits and healthy fruits were examined to determine the content of relevant mineral elements. A micro near-infrared spectrometer collected spectral information, and various pretreatment methods were applied to the near-infrared spectral data. Support vector machine (SVM) modelling using the original data achieved the highest overall recognition accuracy of 84.65% and an F1 value of 84.06%. For identifying fruits without cork spot disease, Autokeras modelled data processed with the SG method, achieving the best accuracy of 90%. These findings establish a reliable basis for the early identification and diagnosis of cork spot disorder in 'Akizuki' pear, enhancing pear production management.

11.
BMC Geriatr ; 23(1): 581, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735369

RESUMO

BACKGROUND: Perioperative brain protection in older patients has been the focus of research recently; meanwhile, exploring the relationship between regional cerebral oxygen saturation (rSO2) and brain function in the perioperative period has been an emerging and challenging area-the difficulties related to the real-time monitoring of rSO2 and the choice of feasible interventions. As an advanced instrument for intraoperative rSO2 monitoring, the clinical application of near-infrared spectrum (NIRS) cerebral oxygen monitoring has gradually increased in popularity and is being recognized for its beneficial clinical outcomes in patients undergoing cardiac and noncardiac surgery. In addition, although sufficient evidence to support this hypothesis is still lacking, the effect of permissive hypercapnia (PHC) on rSO2 has expanded from basic research to clinical exploration. Therefore, monitoring intraoperative rSO2 in older patients with NIRS technology and exploring possible interventions that may change rSO2 and even improve postoperative cognitive performance is significant and clinically valuable. METHODS: This study is a single-center randomized controlled trial (RCT). 76 older patients are enrolled as subjects. Patients who meet the screening criteria will be randomly assigned 1:1 to the control and intervention groups. PHC-based mechanical ventilation will be regarded as an intervention. The primary outcome is the absolute change in the percent change in rSO2 from baseline to the completion of surgery in the intervention and control groups. Secondary outcomes mainly include observations of intraoperative cerebral oxygenation and metabolism, markers of brain injury, and assessments of patients' cognitive function using scale through postoperative follow-up. DISCUSSION: The findings of this RCT will reveal the effect of PHC on intraoperative rSO2 in older patients with nonacute fragile brain function (NFBF) and the approximate trends over time, and differences in postoperative cognitive function outcomes. We anticipate that the trial results will inform clinical policy decision-makers in clinical practice, enhance the management of intraoperative cerebral oxygen monitoring in older patients with comorbid NFBF, and provide guidance for clinical brain protection and improved postoperative cognitive function outcomes. TRIAL REGISTRATION: ChiCTR, ChiCTR2200062093, Registered 9/15/2022.


Assuntos
Cirurgia Colorretal , Laparoscopia , Humanos , Idoso , Hipercapnia , Laparoscopia/efeitos adversos , Cognição , Encéfalo/cirurgia , Oxigênio , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Data Brief ; 50: 109476, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37600593

RESUMO

Densification of agricultural wastes for briquette production has considerable potential to meet the growing energy demand and contribute towards a safe environment worldwide. The datasets contained in this paper are the performance characteristics of raw and torrefied briquettes produced from sawdust (SD), cassava peels (CP), cornhusk (CH), and their blends using a developed piston-type briquetting machine. The physicomechanical, chemical, structural, and combustion indices including the kinetic parameters, were determined using standard methods. The result obtained show that each briquettes sample has the infrared transmittance of C-H, OH, C-O, and C=C with the SD sample having the highest and CP, the lowest. The feedstock mixture and increase in torrefaction temperature enhance the physicomechanical properties of the briquettes through water preconditioning. The combustion characteristics show that the torrefied briquettes and their blends could be co-fired with coal, and are well suited for heating applications and reduce environmental pollution. The activation energy, pre-exponential factor, and R2 values of the briquettes ranged between 39.70-60.76 kJ/mol, 5.52-9.17 min-1, and 0.95-0.98, respectively. The data provided in this paper will therefore be useful for energy enthusiasts and coal engine design, and assist in choosing the appropriate briquette blends with increased calorific value for heating applications.

13.
Biosensors (Basel) ; 13(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37504114

RESUMO

The prevalence of diabetes is rapidly increasing worldwide and can lead to a range of severe health complications that have the potential to be life-threatening. Patients need to monitor and control blood glucose levels as it has no cure. The development of non-invasive techniques for the measurement of blood glucose based on photoacoustic spectroscopy (PAS) has advanced tremendously in the last couple of years. Among them, PAS in the mid-infrared (MIR) region shows great promise as it shows the distinct fingerprint region for glucose. However, two problems are generally encountered when it is applied to monitor real samples for in vivo measurements in this MIR spectral range: (i) low penetration depth of MIR light into the human skin, and (ii) the effect of other interfering components in blood, which affects the selectivity of the detection system. This review paper systematically describes the basics of PAS in the MIR region, along with recent developments, technical challenges, and data analysis strategies, and proposes improvements for the detection sensitivity of glucose concentration in human bodies. It also highlights the recent trends of incorporating machine learning (ML) to enhance the detection sensitivity of the overall system. With further optimization of the experimental setup and incorporation of ML, this PAS in the MIR spectral region could be a viable solution for the non-invasive measurement of blood glucose in the near future.


Assuntos
Diabetes Mellitus , Glucose , Humanos , Glucose/análise , Glicemia/análise , Espectrofotometria Infravermelho/métodos , Pele/química , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/metabolismo
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37453381

RESUMO

Osteoarthritis (OA) is the most common joint disease and the leading cause of disability in elderly individuals. Despite rapid advances in imaging techniques, early OA diagnosis remains a clinical challenge. In the present study, the feasibility of early OA diagnosis was explored via near-infrared spectroscopy (NIRS) combined with aquaphotomics. Synovial fluid samples from 65 cases of OA categorized as mild, moderate, and severe according to theKellgrenandLawrence classification criteria were analyzed via NIRS. The 1st overtone of water (1300-1600 nm) was considered as the research object for an aquaphotomics model, and aquagrams of the mild, moderate, and severe OA cases were generated using 12 water absorption patterns for early OA diagnosis.The aquaphotomics results exhibited clear differences in the region of 1300-1500 nm, and the number of hydrogen bonds of different water species (1412,1424, 1482, and 1496 nm) evidently correlated with OA occurrence and development. With OA progression, the absorption intensity of water molecules without hydrogen bonds (1412 nm/1424 nm) became stronger, while the absorption intensity of water molecules with four hydrogen bonds (1482 nm/1496 nm) decreased.These results together reveal that the established accurate and rapid early OA diagnosis model based on NIRS combined with aquaphotomics is effective and feasible, and that the number of hydrogen bonds can be used as a biomarker for early OA diagnosis.


Assuntos
Osteoartrite , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Idoso , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Fenômenos Químicos , Ligação de Hidrogênio , Água/química
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 122912, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37348273

RESUMO

The interfacial and confined water have long been attractive objects due to their crucial roles in biological, geological processes, etc. In this paper, we investigate the hydrogen-bonded structures of water and their low temperature transitions in the subnano channels of AlPO4-11 for the first time on the basis of infrared spectroscopy. The number of the adsorbed water molecules is estimated to be 8.45 per channel in one unit cell by thermogravimetric analysis. It is found that the confined water molecules are involved in saturated and unsaturated coordination with different hydrogen bond strengths at ambient temperature. The former refers to ice-like four-coordinated water and the latter includes liquid-like structures, Al-coordinated and relatively free water molecules. Unique coordination between water molecules and framework Al sites is responsible for the ice-like structures in the channels above the ice melting point. The appearance of liquid-like structures is closely related to the strong channel confinement, which does not allow the formation of extensive tetrahedral hydrogen-bonded configuration. As temperature decreases, a structural transformation of confined water happens in the channels of AlPO4-11. Isolated small water oligomers and two new components with stronger hydrogen bonds, such as low-density amorphous ice-like structures and a kind of low-density liquid-like structures are preferred. Our results provide important insights into the structural organizations and thermal-dynamic behaviors of confined water in extreme narrow channels.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 299: 122863, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37196551

RESUMO

Fermi resonance (FR), a prevalent phenomenon in molecules, has an important effect in spectrum analysis. As an effective way to change the molecular structure and tune symmetry, high-pressure techniques can often induce FR. Hydroquinone (HQ) is a hydrogen-bonded crystal that tends to form a solid inclusion compound with a suitable guest and has wide applications. Inthiswork, a high-pressure technique was used to investigate α-HQ using high pressure to tune the symmetry to produce FR. Raman and infrared spectra of α-HQ were investigated at ambient pressure, and then Raman spectra under high pressure of α-HQ were investigated up to 19.64 GPa. Results indicated that there were two phase transitions found at about 3.61 and 12.46 GPa. Fundamental FR was not present in α-HQ molecules at ambient pressure. At 3.61 GPa, the first-order phase transition occurred due to the pressure-induced symmetry change, resulting in two Raman modes at 831 cm-1 and 854 cm-1 with the same symmetry, thereby providing evidence that the fundamental FR phenomenon occurred. Furthermore, the pressure-induced changes of the FR parameters were elucidated. Thus pressure provided an effective way to study FR between two asymmetric species.

17.
Sensors (Basel) ; 23(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37177521

RESUMO

For the demand of rapid monitoring of pollution gas disorganized emissions in industrial parks, this paper studies the solar fast tracker system of vehicle-mounted SOF-FTIR (Solar Occultation Flux Fourier Transform Infrared Spectroscopy) system, where the spectrometer directly measures the broadband absorption spectrum of solar radiation light. A fast portable solar tracking system based on PSD (position sensitive detector) is designed, the mathematical model of solar spot position on the PSD surface source is established, and the optimal optical design parameters are simulated using the model. The dead-zone integral separation PID (Proportion Integration Differentiation) control algorithm is used to track the trajectory of the solar, and the light spot position model is used to nonlinearly compensate the output of PID control so that the PID controller has the same control precision and response speed in different error areas. Experimental analysis of the solar tracking performance of the vehicle-mounted SOF-FTIR under static and dynamic conditions, as well as the spectral effects on the measurements under static vehicle, constant speed, and turning driving conditions. The remote sensing application experiment of vehicle-mounted SOF-FTIR pollution gas emission flux was carried out in a tire factory in Hefei City, Anhui Province. A vehicle-mounted SOF-FTIR system realized the qualitative and quantitative analysis of the pollution gas at the boundary of the tire plant and calculated the flux of each component pollution gas. The emission flux of pollution gas was highly consistent with the actual pollution distribution of the tire plant. The results show that the positioning accuracy of PSD in the vehicle tracking experiment can also meet SOF-FTIR requirements for solar tracking. The remote sensing system will be useful in the field of atmospheric environment monitoring, and the mobile monitoring of regional pollutant gases based on solar infrared spectroscopy has application value.

18.
Artigo em Russo | MEDLINE | ID: mdl-37129393

RESUMO

The article presents review of scientific publications on development of laser treatment methods in vitreoretinal surgery. The use of photo-therapy in medicine dates back to ancient times, when people began to use sunlight as treatment of various diseases. The heyday of photo-therapy falls on the second half of the XIX century, which was associated with the invention of first electric lamps. In 1960, T. Maiman developed the world's first laser, revolutionizing precision and control of light delivery. This was the beginning of heyday of laser surgery primarily in ophthalmology, where potential of lasers was instantly recognized. The subsequent discovery of argon laser in 1964 by W. Bridges (USA) marked new era in retinal photo-coagulation. Then new types of lasers with various systems of delivering laser radiation appeared that significantly expanded range of application of laser technologies in ophthalmology and vitreoretinal surgery. Currently, the lasers are applied in oculoplasty, refractive and corneal surgery, in laser support of phacoemulsification of cataract, in treatment of glaucoma, in laser coagulation of retina and thermotherapy. In vitreoretinal surgery laser technologies remain at the level of the XX century. Thus, they are still applied only for endolaser coagulation of retina. And this despite the fact that there is immense potential for applying lasers as "laser scalpel" to remove vitreous humor, epiretinal fibrosis, retinotomy and choroidotomy.


Assuntos
Oftalmologia , Cirurgia Vitreorretiniana , Humanos , Lasers , Retina/cirurgia , Corpo Vítreo/cirurgia
19.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838921

RESUMO

In this paper, a novel hybrid material, entitled histaminium bis(trioxonitrate), with the general chemical formula (C5H11N3)(NO3)2, denoted by HTN was presented. Single-crystal X-ray diffraction was used to determine the structural characteristics of this compound after it was made using a slow evaporation method at room temperature. This compound was elaborated and crystallized to the monoclinic system with space group P21/c, and the lattice parameters obtained were: a = 10.4807 (16)Å, b = 11.8747 (15)Å, c = 16.194 (2)Å, ß = 95.095 (6)°, V = 2007.4 (5)Å3 and Z = 8. The title compound's atomic structure couldbe modeled as a three-dimensional network. Organic cations and nitrate anions were connected via N-H...O and C-H...O hydrogen bonds in the HTN structure. The intermolecular interactions responsible for the formation of crystal packing were evaluated using Hirshfeld surfaces and two-dimensional fingerprint plots. The compound's infrared spectrum, which ranged from 4000 to 400 cm-1, confirmed the presence of the principal bands attributed to the internal modes of the organic cation and nitrate anions. Additionally, spectrofluorimetry and the ultraviolet-visible spectrum was used to investigate this compound. DFT calculations were used to evaluate the composition and properties of HTN. The energy gap, chemical reactivity and crystal stability of HTN were quantified by performing HOMO-LUMO frontier orbitals analysis. Topological analysis (AIM), Reduced Density Gradient (RDG), molecular electrostatic potential surface (MEPS) and Mulliken population were processed to determine the types of non-covalent interactions, atomic charges and molecular polarity in detail.


Assuntos
Nitratos , Teoria Quântica , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
20.
Zhongguo Zhen Jiu ; 43(1): 109-13, 2023 Jan 01.
Artigo em Chinês | MEDLINE | ID: mdl-36633249

RESUMO

To make up for the shortcomings of traditional mild moxibustion, according to the principle and technical operation characteristics of traditional mild moxibustion, combined with temperature control technology, a novel infrared mild moxibustion device is developed, which is capable of real-time accurate temperature control. This novel infrares mild moxibustion device is composed of a host computer and an infrared radiation head. The host computer includes four modules: power supply, human-computer interaction interface, micro control unit (MCU) and drive circuit. The infrared radiation head mainly includes an infrared heater and a temperature sensor. This novel infrared mild moxibustion device is easy to operate. The electrothermal heating tablet can generate infrared radiation of 3 000-13 000 nm. After the temperature of the infrared heater is stabilized, the range of temperature change is ±0.50 ℃, realizing the goal of precise temperature control. In addition, it can operate moxibustion treatment at multiple acupoints at the same time, which is conducive to the dose-effect evaluation of mild moxibustion.


Assuntos
Moxibustão , Humanos , Pontos de Acupuntura , Temperatura , Calefação
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