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A reflective optical fiber sensor that is composed of two Fabry Perot cavities is proposed for temperature and salinity measurement. One of the Fabry Perot cavity which is fabricated by offset splicing is exposed to the ambient directly to sense the ambient salinity, the other is employed to compensate for the temperature coupling effect. A thin layer of the gold film is coated on the refractive index change interface, which makes the spectrum quality is no longer limited by the refractive index difference between the two sides of the interface. By applying the frequency division multiplexing (FDM) technique and cavity length demodulation technology, the measurement range is no longer restricted to the free spectrum range (FSR), which can realize salinity measurement in the full measurement range. The proposed sensor can realize the salinity sensitivity better than 50 nm/‰ and temperature sensitivity of 6.85 nm/°C in the cavity length domain. It is promising for salinity measurement application for its merits of low cost, easy fabrication, and long sensing distance. [ABSTRACT FROM AUTHOR]

A novel magnetic field measurement method based on the magneto-volume effect is proposed. The magnetic field sensing structure fabricated by the proposed measurement method is made by the magnetic fluid (MF) partially filled into the hollow core fiber (HCF). The presence of air provides conditions for the change of MF volume with the magnetic field in the proposed sensing structure. Therefore, the magneto-volume effect is introduced into the magnetic field sensing mechanism. From 109.6 to 125.8 Gs, the peak wavelength shift is −65480 pm and the sensitivity is −4219.15 pm/Gs, which is 28.16 times higher than that of the fabricated contrast sensing structure. The sensitivity of the magnetic field sensing structure is greatly improved by introducing the magneto-volume effect compared with the contrast sensing structure. The response time and recovery time of the sensing structure are equally 0.2 s. Therefore, the sensing structure has high sensitivity, good linearity, and short response time, which has potential application prospects in magnetic field sensing. [ABSTRACT FROM AUTHOR]

A magnetic field measurement method based on the magneto-volume effect of magnetic fluid (MF) and Fabry–Perot (FP) interferometer (FPI) is proposed, which has higher magnetic field sensitivity and shorter response time than the traditional optical fiber methods. The MF is partially injected into the fabricated FP cavity composed of two sections of SMFs and a capillary glass tube (CGT), where the FPI is made up of optical fiber end face and MF end face. When the external magnetic field is applied to the sensor, the volume change of MF will cause the change of air cavity length. Therefore, the reflection spectrum changes with external magnetic field due to the magneto-volume effect of MF. Experimental results show that the magnetic field sensor shows a sensitivity of 268.81 pm/Gs from 15.5 to 139.7 Gs even with a small amount of MF. The response time is 0.2 s at a step magnetic field of 7.7, 31.0, 46.5, and 139.7 Gs. In this work, the magnetic field sensor boasts high sensitivity, good repeatability, short response time, and low cost, which shows a great potential in applications. [ABSTRACT FROM AUTHOR]

A highly sensitive reflective Fabry–Perot (FP) magnetic field sensor using magnetic fluid (MF) based on the Vernier effect is presented and experimentally verified. Capillary action acts as an injection of MF into an FP cavity, which is composed of a single-mode fiber (SMF), capillary glass tube, and a short section of SMF coated with gold film. Vernier effect is formed by the MF cavity and air cavity in the FP magnetic field sensor, where the surface of MF is concave. The refractive index (RI) of MF depends on the magnetic field, and therefore, the wavelength of the reflection spectrum of the fabricated sensor can be sensitive to the magnetic field. The magnetic field sensor’s sensitivity is up to 1.02602 nm/Gs from 118.768 to 166.261 Gs, and the resolution is 0.0078 Gs. The sensor shows good linearity within the range of 71.317–231.751 Gs, and the linearity is larger than 0.999. In this article, a new type FP cavity fabricated by splicing SMF inside the capillary glass tube is proposed, and MF can be injected into the FP cavity, which can also be applied to other liquids to generate Vernier effect. The concave surface of MF is creatively applied to the sensors, and the experimental verification is carried out in a capillary glass tube, which provides a basis on the capillary action of other fluids in fiber sensing. [ABSTRACT FROM AUTHOR]

In this article, a reflective-type optical fiber probe, which can measure salinity and temperature simultaneously, is proposed. The proposed probe integrates Mach–Zehnder interferometer and Fabry–Perot interferometer in the same channel skillfully and effectively, which makes it possible to integrate more information into the sensor. The reflected spectrum is improved greatly by adopting special sputtering technology. The spectrums of Mach–Zehnder and Fabry–Perot are separated by applying the frequency division multiplex technique. The simulation and experimental results prove that the proposed probe has a highly sensitive response to temperature and salinity. The experiment result verifies that the salinity sensitivity is up to 2.7 nm/‰ and the temperature sensitivity is better than 0.4 nm/°C. The reflective probe makes the sensor easy to use and paves the way for practical application. [ABSTRACT FROM AUTHOR]

For the purpose of monitoring seawater temperature, a novel Mach–Zehnder (MZ) temperature-sensing structure with a wedge-shaped open cavity is presented and experimentally studied in this article. The open-cavity structure realizes the direct contact between the sensing optical path and the external environment, and ensures the high sensitivity of the structure. At the same time, it achieves not only low loss by direct fusion splicing instead of dislocation fusion splicing, but also low cost by hydrofluoric (HF) etching instead of femtosecond processing. In addition, the temperature sensitivity of the sensor structure proposed in this article can reach 1.5 nm/°C without temperature-sensitive material filled, and 6 nm/°C with silicone oil filled. Moreover, the resolution of the sensing structure is 0.24 °C based on the criterion of $3\sigma $. [ABSTRACT FROM AUTHOR]

In this work, the MWO (M = Co, Ni) nanoparticles were successfully synthesized by a facile one-step hydrothermal method and used as novel anode materials for LIBs. The micromorphology of obtained CoWO and NiWO was uniform nanoparticles with the size of ~60 and ~40 nm, respectively, by structural characterization including X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). When tested as lithium-ion battery anode, CoWO nanoparticles exhibited a stabilized reversible capacity of 980 mA h g at 200 mA g after 120 cycles and 632 mA h g at 1000 mA g even after 400 cycles. And, the discharge capacity was as high as 550 mA h g at the 400th cycle for NiWO nanoparticles. The excellent electrochemical performance could be attributed to the unique nanoparticles structure of the materials, which can not only shorten the diffusion length for electrons and lithium ions but also provide a large specific surface area for lithium storage. [ABSTRACT FROM AUTHOR]

• The magnetic field sensor composed of an ultra-short FPI filled with oil-based magnetic fluid cascaded with a bending coated single-mode-fiber MZI is proposed. • The FPI with ultra-short cavity (about 20 μm) composed of two sections of single mode fiber and a hollow core fiber drilled through by femtosecond laser. • The sensitivities of magnetic field and temperature are up to 240 pm/Gs and −2310 pm/℃ respectively. A fiber magnetic field sensor with temperature compensation is put forward and experimentally verified by utilizing Fabry-Perot interferometer (FPI) and multimode interferometer (MI). The FPI with ultra-short cavity (about 20 μm), which is proposed to improve the spectrum contrast after being filled with oil-based magnetic fluids (MF) and achieve the sensing of magnetic field, is drilled through by femtosecond laser. The FPI is composed of two sections of single mode fiber and a hollow core fiber, which is named as single mode fiber-hollow core fiber-single mode fiber (SHS). The MI composed of the coated-fiber-loop, which is only sensitive to temperature, is proposed to compensate the temperature on the sensing of magnetic field. The fiber loop is fabricated by only bending a section of coated single mode fiber (SMF). According to the experiment results, the spectrum visibility of magnetic field sensing part can be improved by 3.1 times by shortening the Fabry-Perot (FP) cavity length. The interference wavelength increases nonlinearly from 0 to 69.1 Gs while linearly from 69.1 to 137.7 Gs. In addition, its temperature sensitivity is −0.20 nm/℃ from 23.0 to 42.9 ℃. Moreover, the sensitivity of MI is −2.31 nm/℃ from 23.0 to 42.9 ℃. It could be used to compensate the temperature influence effectively. The structure boasts characteristics of simple manufacture, low cost and highly-sensitive, which can be applied in the fields of magnetic field sensing. [ABSTRACT FROM AUTHOR]

Many published studies reflect the growing application of complementary and alternative medicine, particularly Chinese herbal medicine (CHM) use in combination with conventional cancer therapy for advanced non-small cell lung cancer (NSCLC), but its efficacy remains largely unexplored. The purpose of this study is to evaluate the efficacy of CHM combined with conventional chemotherapy (CT) in the treatment of advanced NSCLC. Publications in 11 electronic databases were extensively searched, and 24 trials were included for analysis. A sum of 2,109 patients was enrolled in these studies, at which 1,064 patients participated in CT combined CHM and 1,039 in CT (six patients dropped out and were not reported the group enrolled). Compared to using CT alone, CHM combined with CT significantly increase one-year survival rate (RR = 1.36, 95% CI = 1.15–1.60, p = 0.0003). Besides, the combined therapy significantly increased immediate tumor response (RR = 1.36, 95% CI = 1.19–1.56, p<1.0E−5) and improved Karnofsky performance score (KPS) (RR = 2.90, 95% CI = 1.62–5.18, p = 0.0003). Combined therapy remarkably reduced the nausea and vomiting at toxicity grade of III–IV (RR = 0.24, 95% CI = 0.12–0.50, p = 0.0001) and prevented the decline of hemoglobin and platelet in patients under CT at toxicity grade of I–IV (RR = 0.64, 95% CI = 0.51–0.80, p<0.0001). Moreover, the herbs that are frequently used in NSCLC patients were identified. This systematic review suggests that CHM as an adjuvant therapy can reduce CT toxicity, prolong survival rate, enhance immediate tumor response, and improve KPS in advanced NSCLC patients. However, due to the lack of large-scale randomized clinical trials in the included studies, further larger scale trials are needed. [ABSTRACT FROM AUTHOR]

• The proposed method realizes the large dynamic range and the high accuracy demodulation with less extra computation, which integrates the advantages of DGT and phase methods. • By applying phase difference compensation technology, the OPD demodulation resolution achieves 45.37 pm, and the demodulation accuracy improves about 10,000 times. • The proposed method can also combine with other methods for improving the demodulation accuracy. A novel method, which is based on the phase difference between the filtered spectrum and simulated spectrum, is proposed to compensate for the optical path difference (OPD) demodulation error of the interferometer sensors. With applying the phase difference technology, large dynamic range OPD demodulation with high accuracy is realized. Its principle is deduced by theoretical analysis. The numerical simulation is conducted in the presence of noise, amplitude variation, and constant offset, verifies that the proposed method is robust. The strain experiment result shows that the demodulation resolution is 45.37 pm at the cavity length of around 328 μm. The demodulation accuracy improves about 10,000 times compares with the DGT method, and the demodulation resolution is achieved to the same order as the most advanced method with less computation. And the phase difference technology can be applied to other demodulation methods for high demodulation accuracy. [ABSTRACT FROM AUTHOR]