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1.
Environ Sci Technol ; 53(19): 11294-11301, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31461620

RESUMEN

China has recently implemented broad strategies aimed at achieving a circular economy by providing subsidies for the remanufacture industry and setting a target of 15% increase in energy efficiency in industrial production across sectors, among other strategies. Here, we examine the environmental implications of these policies in the context of engine remanufacture, using an environmental computable general equilibrium (CGE) model. Results indicate that both the subsidy policy and energy efficiency improvement target can contribute to economic growth and emission reductions, but the subsidy policy is estimated to have far greater impacts. The implementation of both can reinforce each other, generating higher economic and environmental benefits than the sum of each occurrence alone. Another major finding from our model is that an additional remanufactured engine only displaces 0.42 (90% confidence interval from 0.32 to 0.47) of a new engine (comprised of new parts), mainly because the lower prices of remanufactured engines lead to greater consumption. This ratio is much lower than the 1:1 perfect displacement commonly assumed in life cycle assessment (LCA) studies. Overall, our study suggests that the subsidizing of engine remanufacture in China can help promote the industry, improve overall economic welfare, and contribute to environmental targets. Our study also contributes to the estimation of more realistic product displacement ratios in LCA.


Asunto(s)
Desarrollo Económico , Industrias , China , Comercio , Modelos Teóricos
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3087-91, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26978914

RESUMEN

The CVD graphene was chosen as the Raman enhancement substrate, graphene-enhanced Raman scattering(GERS) of dipolar molecule DREP were explored with a laser wavelength λ = 532 nm of micro-Raman spectroscopy. Upon comparison of the raman signal of DREP molecular latched to a graphene/SiO2 substrate and to a bare SiO2substrate, we found that the Raman signal of pure DREP molecule basically does not exist at low concentrations, until it reaches a certain concentration of 1 x 10⁻5 mol · L⁻¹, its Raman signal emerging and as the increasing of the concentration, Raman signal and fluorescence signal all increase. However, the raman signal of DREP molecular on the grapheme occur at the concentration of 1 x 10⁻7 mol · L⁻¹ and as the increasing of concentration, the raman signal increasing quickly but the fluorescence signal is not obvious. The studies were shown that graphene can achieve the Raman signal of DREP molecule enhancement, and can quench fluorescent backing off, increase the ratio of Raman signal and fluorescence signals. Comparing the GERS of DREP and DR1P molecules with different molecular dipole moment, indicating that the greater the dipole moment, the greater the enhancement factor, the degree of enhancement is stronger. Finally, we analyze the mechanism of Raman enhancement about DREP molecule on the grapheme. The dipole molecular is a pyrene terminal tethered a azobenzene molecular that was modified. There will happen the electron transfer of the pyrene terminal on the graphene interface through π-π interactions, changing the energy level of grapheme and leading to a p-doping. The mechanism of Raman enhancement are chemical mechanisms. The study of GERS of DREP molecular can help the comprehension of grapheme and the mechanism of grapheme enhanced raman scattering, for example the transfer of grapheme electron, the theory of chemical enhancement mechanism and how to separate the chemical enhancement mechanism from electromagnetic enhancement mechanism.

3.
Opt Express ; 22(19): 22937-51, 2014 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-25321764

RESUMEN

Multi-wavelength regeneration free of inter-channel crosstalk is desirable for wavelength division multiplexing (WDM) systems, especially from the cost-effectiveness point of view. This paper presents the design rules of time-interleaved multi-wavelength 2R regeneration systems based on data-pump four wave mixing (FWM) effect, and several key factors, such as FWM bandwidth, wavelength assignment, and duty cycle, are comprehensively taken into account. The total data rate of time-interleaved WDM regeneration systems along with polarization multiplexing or bidirectional transmission are discussed, which are mainly determined by temporal overlap, spectral broadening and FWM bandwidth. As two examples, an eight-wavelength unidirectional regenerator using polarization multiplexing is designed by optimizing the fiber birefringence, and a six-wavelength bidirectional regenerator is demonstrated by experiment. Each is expected to have a total data rate of about 200 Gb/s for the optical RZ-OOK signals, and the wavelength number is increased at the expense of spectral efficiency.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Dispositivos Ópticos , Procesamiento de Señales Asistido por Computador , Telecomunicaciones/instrumentación , Birrefringencia , Diseño de Equipo
4.
Ultrasonics ; 141: 107331, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38685139

RESUMEN

Different from the traditional frequency-mixing technique which employs a contacting transducer, the laser-induced acoustic nonlinear frequency-mixing detection technique utilizes a laser source to instigate crack motion and generate acoustic waves. Thus, apart from the temperature oscillation induced by the pump laser, the "basic temperature" originating from the probe laser can also influence the crack. This additional variable complicates the contact state of the crack, yielding a more diverse range of nonlinear acoustic signal attributes. In light of this, our study enhances the conventional opto-acoustic nonlinear frequency mixing experimental setup by integrating an independent heating laser beam. This modification isolates the impact of the "basic temperature" on crack width while also dialing down the probe laser power to mitigate its thermal effects. To amplify the sensitivity of crack detection, we deliberated on the optimal laser source parameters for this setup. Consequently, our revamped system, paired with fine-tuned parameters, captures nonlinear acoustic signals with an enriched feature set. This investigation can provide support for the non-contact opto-acoustic nonlinear frequency mixing technique in the detection and evaluation of micro-cracks.

5.
Ultrasonics ; 139: 107288, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38513438

RESUMEN

Photo-thermal modulation-based nonlinear opto-acoustic frequency-mixing technique is an effective method for detecting micro-cracks. When using this technique for micro-crack detection, the selection of laser source parameters is particularly crucial. Compared to traditional piezo-transducer-based mixing techniques, the characteristic of using a laser as the detection source is the presence of thermal effects. The thermal effect caused by laser irradiation on the sample surface can not only generate acoustic waves but also affect the crack state, thus influencing nonlinear signals. In this paper, an experimental setup using photo-thermal modulation-based nonlinear opto-acoustic frequency-mixing technique has been set up to investigate the thermal effects of the probe laser source. In addition, a corresponding physical model has been established to discuss the physical mechanisms revealed by the experimental results. This study provides a basis for selecting appropriate probe source parameters and scanning positions of laser sources when detecting micro-cracks using the photo-thermal modulation-based nonlinear opto-acoustic frequency-mixing technique.

6.
Exp Ther Med ; 27(1): 36, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38125357

RESUMEN

Local ulcerative cutaneous hemorrhage resulting from breast cancer profoundly effects the quality of life of patients, at times even posing a threat to life. While early diagnosis rates of breast cancer have shown improvement, some patients may present at an advanced stage upon consultation. Presently, there is no standardized treatment approach for these patients. In this context, the present study presented two case studies detailing the use of interventional embolization chemotherapy for addressing severe local ulcerative hemorrhage associated with breast cancer. Post-treatment, there was a notable amelioration in the mammary ulceration among the patients, an elevated hemoglobin level compared with baseline and a consequent enhancement in their overall quality of life. These cases may serve as valuable references for the management of such clinical situations.

7.
Opt Lett ; 38(19): 3803-6, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24081057

RESUMEN

We captured stable self-oscillations of a toroidal bubble moving away from a laser propelled cavity object in water using a high-speed imaging system. The entire laser propelling process generates a hemispherical bubble, two toroidal bubbles, and a microbubble cluster. The hemispherical bubble is formed by laser breakdown in water. The toroidal bubbles are formed by the variation of the pressure field as a result of the propagation, reflection, and convergence of the laser plasma shockwave in the cavity.

8.
Environ Sci Technol ; 47(22): 13053-9, 2013 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-24117335

RESUMEN

Active disassembly (AD) uses innovative materials that can perform a designed disassembly action by the application of an external field. AD provides improvements over current disassembly processes by limiting machine or manual labor and enabling batch processing for end-of-life products. With improved disassembly operations, more reuse of components and purer recycling streams may be seen. One problem with AD, however, has been with the single-field actuation because of the probability of accidental disassembly. This presentation will discuss the application of shape memory polymer (SMP) nanocomposites in a new AD process. This novel AD process requires multiple-field actuation of the SMP nanocomposite fastener. In the analysis of this AD process, thermal and magnetic field tests were performed on the SMP nanocomposite. From these tests, finite-element analysis was performed to model and simulate the multiple-field AD process. The results of the simulations provide performance variables for the AD process and show a better performance time for the SMP nanocomposite fastener than for a comparable SMP fastener.


Asunto(s)
Simulación por Computador , Nanocompuestos/química , Polímeros/química , Fenómenos Magnéticos , Modelos Teóricos , Temperatura de Transición
9.
Eur J Med Chem ; 257: 115492, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37210838

RESUMEN

Multiple myeloma (MM) is a hematologic neoplasm of plasma cells that is currently deemed incurable. Despite the introduction of novel immunomodulators and proteasome inhibitors, MM remains a challenging disease with high rates of relapse and refractoriness. The management of refractory and relapsed MM patients remains a formidable task, primarily due to the emergence of multiple drug resistance. Consequently, there is an urgent need for novel therapeutic agents to address this clinical challenge. In recent years, a significant amount of research has been dedicated to the discovery of novel therapeutic agents for the treatment of MM. The clinical utilization of proteasome inhibitor carfilzomib and immunomodulator pomalidomide has been successively introduced. As basic research continues to advance, novel therapeutic agents, including panobinostat, a histone deacetylase inhibitor, and selinexor, a nuclear export inhibitor, have progressed to the clinical trial and application phase. This review aims to furnish a comprehensive survey of the clinical applications and synthetic pathways of select drugs, with the intention of imparting valuable insights for future drug research and development geared towards MM.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Panobinostat/uso terapéutico , Inhibidores de Histona Desacetilasas/uso terapéutico , Inhibidores de Proteasoma , Factores Inmunológicos/farmacología , Factores Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
10.
Eur J Med Chem ; 256: 115434, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37148849

RESUMEN

Rheumatoid arthritis (RA) is a persistent autoimmune ailment that is typified by the development of pannus, proliferation of synovial lining cells, microvascular neogenesis, infiltration of interstitial inflammatory cells, and destruction of cartilage and bone tissue. The disease not only imposes physical pain and economic burden on patients, but also results in a significant decline in their quality of life, rendering it a leading cause of disability. General treatment and drugs are commonly employed to alleviate the condition and symptoms of RA. Cyclooxygenase (COX), janus kinase (JAK), glucocorticoid receptor (GR) et al. have been identified as the main therapeutic targets for RA. This article provides a comprehensive review of the clinical applications and synthetic routes of 26 representative drugs for the treatment of RA, with the aim of facilitating the discovery of more effective new drugs for the treatment of this debilitating disease.


Asunto(s)
Artritis Reumatoide , Calidad de Vida , Humanos , Artritis Reumatoide/tratamiento farmacológico , Huesos
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(2): 319-22, 2011 Feb.
Artículo en Zh | MEDLINE | ID: mdl-21510371

RESUMEN

Laser-induced breakdown spectroscopy (LIBS) has been used to detect the elements of 2519A aluminum alloy by Nd : YAG laser in the present paper. The atomic spectral lines of Al and Cu were observed using a portable spectrometer. The impacts of lens-to-sample distance, probe angle, laser pulse energy, observation height and ambient pressure on the line intensities were studied. The results show that all these experimental parameters have great influence on the precision of LIBS such as line intensity, signal to background ratio and repeatability. Finally, the best results can be observed by using the optimum experimental conditions.

12.
Nat Commun ; 11(1): 2274, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32371924

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Nat Commun ; 11(1): 161, 2020 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-31919426

RESUMEN

Chiral recognition, such as enantioselective interactions of enzyme with chiral agents, is one of the most important issues in the natural world. But artificial chiral receptors are much less efficient than natural ones. For tackling the chiral recognition and enantiomer excess (ee) analysis, up until now all the fluorescent receptors have been developed based on fluorescence intensity changes. Here we report that the chiral recognition of a large number of chiral carboxylic acids, including chiral agrochemicals 2,4-D, is carried out based on fluorescent colour changes rather than intensity changes of AIEgen rotors. Moreover, the fluorescence wavelength of the AIEgen rotor linearly changes with ee of the carboxylic acid, enabling the ee to be accurately measured with average absolute errors (AAE) of less than 2.8%. Theoretical calculation demonstrates that the wavelength change is ascribed to the rotation of the AIEgen rotor upon interaction with different enantiomers.

14.
Org Lett ; 22(5): 1836-1840, 2020 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-32049536

RESUMEN

The aggregation-induced emission (AIE) mechanism of restriction of double-bond rotation (RDBR) was utilized to design an excellent solid emitter and sensor for the first time. Thus, cis-tetraphenylethylene (TPE) macrocycle diammoniums were synthesized and bound to a DNA chain by its two ammonium arms. The formed TPE dicycle at the cis position restricted the rotation of the double bond in both the ground and excited states, resulting in AIE enhancement, chiroptical performance enhancement, and sensing enhancement.

15.
Zhong Yao Cai ; 31(10): 1503-5, 2008 Oct.
Artículo en Zh | MEDLINE | ID: mdl-19230399

RESUMEN

OBJECTIVE: To study the chemical constituents of Elaeocarpus sylvestris. METHODS: The compounds were isolated by chromatographic methods and their structures were elucidated by physico-chemical properties and spectral analysis. RESULTS: Six compounds were isolated and identified as: 2-hydroxy-benzaldehyde (1), coniferyl alcohol (2), umbelliferone (3), scopoletin (4), beta-sitosterol (5), daucosterol (6). CONCLUSION: All above compounds are isolated from Elaeocarpus Genus for the first time.


Asunto(s)
Benzaldehídos/aislamiento & purificación , Catecoles/aislamiento & purificación , Elaeocarpaceae/química , Fenoles/aislamiento & purificación , Plantas Medicinales/química , Umbeliferonas/aislamiento & purificación , Benzaldehídos/química , Catecoles/química , Fenoles/química , Hojas de la Planta/química , Escopoletina/química , Escopoletina/aislamiento & purificación , Sitoesteroles/química , Sitoesteroles/aislamiento & purificación , Espectrofotometría Ultravioleta , Umbeliferonas/química
16.
Biomed Pharmacother ; 97: 697-707, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29102913

RESUMEN

We report a study on inhibition of human oral squamous cell carcinoma in vitro and in vivo, using novel photosensitizer (PS) aloe emodin (AE) mediated photodynamic therapy (PDT). Distinct morphology changes of oral mucosa carcinoma KB cells were observed under an optical microscope and cell migrations were inhibited owing to AE-PDT. The cell proliferation was blocked in G1 phase and the apoptosis increase were both caused by massive reactive oxygen species (ROS) generated from photoactivated AE. The upregulation of Caspase-3 and Bax protein levels and downregulation of Bcl-2 protein levels were observed after AE-PDT. The survival time of tumor mouse was prolonged without side effects ascribed to AE-PDT and its inhibitory effect on mice transplantation tumors was significant. It is indicated that AE mediated PDT is an innovative way to oral cancer treatment with the dominances of effectivity, minimal invasion, tissue integrity retention and none side effects on main organs.


Asunto(s)
Antraquinonas/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de la Boca/tratamiento farmacológico , Fotoquimioterapia/métodos , Animales , Antraquinonas/efectos adversos , Antraquinonas/farmacología , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/patología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Trasplante de Neoplasias , Fotoquimioterapia/efectos adversos , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/efectos adversos , Fármacos Fotosensibilizantes/farmacología , Especies Reactivas de Oxígeno/metabolismo , Tasa de Supervivencia
17.
Org Lett ; 20(2): 373-376, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29303592

RESUMEN

This paper reports that cis-TPE dicycles emit strong fluorescence, while the gem dicycles show almost no emission in solution, demonstrating that the free rotation restriction of the double bond at the excited state is the key factor for AIE effects.

18.
Materials (Basel) ; 10(4)2017 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-28772702

RESUMEN

As a prospective candidate material for surface coating and repair applications, nickel-based superalloy Inconel 718 (IN718) was deposited on American Iron and Steel Institute (AISI) 4140 alloy steel substrate by laser engineered net shaping (LENS) to investigate the compatibility between two dissimilar materials with a focus on interface bonding and fracture behavior of the hybrid specimens. The results show that the interface between the two dissimilar materials exhibits good metallurgical bonding. Through the tensile test, all the fractures occurred in the as-deposited IN718 section rather than the interface or the substrate, implying that the as-deposited interlayer bond strength is weaker than the interfacial bond strength. From the fractography using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS), three major factors affecting the tensile fracture failure of the as-deposited part are (i) metallurgical defects such as incompletely melted powder particles, lack-of-fusion porosity, and micropores; (ii) elemental segregation and Laves phase, and (iii) oxide formation. The fracture failure mechanism is a combination of all these factors which are detrimental to the mechanical properties and structural integrity by causing premature fracture failure of the as-deposited IN718.

19.
Materials (Basel) ; 10(11)2017 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-29120374

RESUMEN

AISI 4140 powder was directly deposited on AISI 4140 wrought substrate using laser engineered net shaping (LENS) to investigate the compatibility of a LENS-deposited part with the substrate. Tensile testing at room temperature was performed to evaluate the interface bond performance and fracture behavior of the test specimens. All the samples failed within the as-deposited zone, indicating that the interfacial bond is stronger than the interlayer bond inside the deposit. The fracture surfaces were analyzed using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS). Results show that the tensile fracture failure of the as-deposited part is primarily affected by lack-of-fusion defects, carbide precipitation, and oxide particles inclusions, which causes premature failure of the deposit by deteriorating the mechanical properties and structural integrity.

20.
Ultrasonics ; 64: 58-61, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26298599

RESUMEN

The interaction of laser-generated Lamb waves propagating in a plate with a sharp-angle conical hole was studied experimentally and numerically. Part of the energy of the incident wave is trapped within the conic area in two ways: the antisymmetric Lamb wave orbiting the center of the hole and the wave localized at the acute edge. Parameters and conditions for optimal conversion of the incident wave into the trapped modes were studied in this work. Experiments were performed using the laser stroboscopic shearography technique, which delivers the time evolution of the acoustic field in the whole area of interest. The effect of trapping can be used for efficient damping, similar to the one-dimensional acoustical black hole effect.

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