High-efficiency Interface Research Articles

High-efficiency interface between multi-mode and single-mode fibers.

Multi-mode fibers (MMFs) and single-mode fibers (SMFs) are widely used in optical communication networks. MMFs are the practical choice in terms of cost in applications that require short distances. Beyond that, SMFs are necessary because of the modal dispersion in MMFs. Here, we present a method capable of interfacing an MMF with an SMF using a re-programmable multi-plane light conversion scheme (MPLC). We demonstrate that only three phase modulations are necessary to achieve MMF-SMF coupling efficiencies from 30% to 70%, i.e., an insertion loss from 5 dB to 1.5 dB, for MMFs with core diameters up to 200 μm. We show how the obtained coupling efficiency can be recovered if the output field of the MMF changes entirely, e.g., through strong deformation of the fiber, by simple monitoring of the field. Furthermore, we test the influence of the resolution of both essential devices (field reconstruction and MPLC) on coupling efficiencies. We find that commercially available devices with increased speed and efficiency, such as wavefront sensors and deformable mirrors, are sufficient for establishing an MMF-SMF interface that auto-corrects any decoupling in the kilohertz regime.

Versatile Janus structured integrated device for photodynamic heat transformation

The interface photodynamic heat transformation technology is one of the most promising solar energy application technologies. Despite the vigorous development of high-efficiency interface conversion materials, hindrances such as low conversion rate and poor stability are still encountered. Herein, the Cu0.95V2O5 (CuVO) protected by the Janus structure based on copper foam (CF) was successfully prepared and applied to photodynamic steam generation for the first time. Among them, the epoxy resin coating ensures the stability of CuVO in hostile environments and promotes the absorption rate of the absorber in the infrared band. The evaporation rate of the Janus evaporator stabilized at 1.75 kg m−2 h−1 after 1 h in real seawater (1 kw m−2). The super-hydrophilic/hydrophobic Janus structure was applied to sewage treatment and has achieved an ion removal rate of up to 99.9%. Meanwhile, the absorber has excellent light response performance, and can accurately monitor the outdoor sun illumination in a small surface temperature range. In this study, the epoxy-protected Janus evaporator demonstrates a new paradigm for photodynamic water treatment with outstanding characteristics such as low heat loss, high evaporation rate, super salt resistance, and self-cleaning performance, providing an effective strategy for the application of photodynamic materials as a sensor.

Faradaic Heterojunction Arrays Enable Fully Solar-Powered Energy Conversion and Storage via High-Efficiency Interface Charge-Transfer

Faradaic Heterojunction Arrays Enable Fully Solar-Powered Energy Conversion and Storage via High-Efficiency Interface Charge-Transfer

Intracellular silver speciation by coupling capillary electrophoresis to ICP-MS integrating a high performance spiral flow spray chamber

The study of silver species and their distribution/transformation in cell interior is of high significance for the elucidation of toxicology of silver nanoparticles (AgNPs). The intracellular speciation of dissolved Ag(I) and AgNPs was reported. The analytical platform integrated capillary electrophoresis (CE) to inductively coupled plasma-mass spectrometry (ICP-MS) incorporating a high efficiency interface and a high performance spiral flow spray chamber (SFSC). The interface and the SFSC provide a favorable detection limit of 87 ng L−1 for the dissolved Ag(I). Total silver content was quantified by ICP-MS subject to digestion of the cell lysate, and quantification of AgNPs was carried out by subtraction. The speciation of dissolved Ag(I) and AgNPs in culture medium and HepG2 cells was performed, with RSDs of <3% for relative peak area and <2% for migration time, as well as spiking recoveries of 93.8%–94.3% in opti-MEM and 92.7%–106.6% in cell lysate. The present study indicated higher solubility of AgNPs in the cell interior with respect to that in the culture medium, due to oxidative stress or acidic microenvironment in the cancer cells.

A High Efficiency AC/DC NVC-PSSHI Electrical Interface for Vibration-Based Energy Harvesters

Energy harvesting is the process of capturing the local ambient energy and converting it into useful energy. Piezoelectric energy harvesters (PEHs) are one of the solutions to convert vibration energy to electrical energy. An electrical interface is needed to bridge between the piezoelectric energy harvester and the energy storage element. A high-efficient AC/DC converter is designed for a low vibration power harvester with the milli- or micro-watt range power. This paper reports a novel self-powered high-efficiency interface to rectify the AC voltage generated by a vibration energy harvester to DC voltage. The reported interface consists of a triggering circuit and a Negative Voltage Converter (NVC) combined with a Parallel Synchronized Switch Harvesting on Inductor (PSSHI) forming the NVC-PSSHI. The analytical model and simulation of the designed NVC-PSSHI interface were derived and performed, respectively. The targeted input voltage, frequency and DC loading conditions were 3 Vpp to 7 Vpp, 100 Hz to 500 Hz and 5 $\text{k}\Omega $ to 30 $\text{k}\Omega $ , respectively. Experiments with a PEH were also performed to validate the analytical and simulation results. The maximum efficiency of the designed NVC-PSSHI interface reached 82.1% from the PEH experiment. The NVC-PSSHI interface efficiency was higher than the traditional PSSHI interface by up to 23.4%.

An Efficient Interface Circuit for Miniature Piezoelectric Energy Harvesting with P-SSHC

A miniature and high-efficiency interface circuit based on parallel synchronous switch harvesting on capacitors (P-SSHC) for piezoelectric energy harvesting (PEH) is proposed in this paper. This interface circuit consists of a two-stage synchronous rectifier and the P-SSHC circuit. The two-stage synchronous rectifier, composed of a negative voltage converter (NVC) and an active diode (AD), achieves higher efficiency compared with the full-bridge rectifier (FBR). In addition, the two-stage synchronous rectifier detects the zero-crossing moment of the input current; therefore, an extra current zero-crossing detection circuit is eliminated, which simplifies the structure of the interface circuit, reduces power consumption and improves peak converting efficiency. The P-SSHC circuit aims to improve the power extraction capability of the rectifier. The P-SSHC achieves considerable voltage flipping efficiency with very small volume compared to the parallel synchronized switch harvesting on inductor (P-SSHI), which is more suitable for volume sensitive applications. The proposed interface circuit is designed in SMIC 0.35[Formula: see text][Formula: see text]m CMOS process. Simulation results show that it achieves a [Formula: see text] output power improvement compared with FBR for the case of a 3.4[Formula: see text]V open-circuit voltage, the voltage flipping efficiency is as high as 83.6% and the peak power converting efficiency is up to 91.5%. The overall volume of the capacitors used in this paper is only 0.6[Formula: see text]mm3, which is much smaller than the inductor used by conventional P-SSHI interface circuit.

A Web Services Discovery Approach Based on Mining Underlying Interface Semantics

In recent years, Web service discovery has been a hot research topic. In this paper, we propose a novel Web services discovery approach, which can mine the underlying semantic structures of interaction interface parameters to help users find and employ Web services, and can match interfaces with high precision when the parameters of those interfaces contain meaningful synonyms, abbreviations, and combinations of disordered fragments. Our approach is based on mining the underlying semantics. First, we propose a conceptual Web services description model in which we include the type path for the interaction interface parameters in addition to the traditional text description. Then, based on this description model, we mine the underlying semantics of the interaction interface to create index libraries by clustering interaction interface names and fragments under the supervision of co-occurrence probability. This index library can help provide a high-efficiency interface that can match not only synonyms but also abbreviations and fragment combinations. Finally, we propose a Web service Operations Discovery algorithm (OpD). The OpD discovery results include two types of Web services: services with “Single” operations and services with “Composite” operations. The experimental evaluation shows that our approach performs better than other Web service discovery methods in terms of both discovery time and precision/recall rate.

An Input-Powered High-Efficiency Interface Circuit with Zero Standby Power in Energy Harvesting Systems

This study presents an input-powered high-efficiency interface circuit for energy harvesting systems, and introduces a zero standby power design to reduce power consumption significantly while removing the external power supply. This interface circuit is composed of two stages. The first stage voltage doubler uses a positive feedback control loop to improve considerably the conversion speed and efficiency, and boost the output voltage. The second stage active diode adopts a common-grid operational amplifier (op-amp) to remove the influence of offset voltage in the traditional comparator, which eliminates leakage current and broadens bandwidth with low power consumption. The system supplies itself with the harvested energy, which enables it to enter the zero standby mode near the zero crossing points of the input current. Thereafter, high system efficiency and stability are achieved, which saves power consumption. The validity and feasibility of this design is verified by the simulation results based on the 65 nm CMOS process. The minimum input voltage is down to 0.3 V, the maximum voltage efficiency is 99.6% with a DC output current of 75.6 μA, the maximum power efficiency is 98.2% with a DC output current of 40.4 μA, and the maximum output power is 60.48 μW. The power loss of the entire interface circuit is only 18.65 μW, among which, the op-amp consumes only 2.65 μW.

Silicon Integrated 280 GHz Imaging Chipset With 4&lt;formula formulatype="inline"&gt;&lt;tex Notation="TeX"&gt;$\times$&lt;/tex&gt; &lt;/formula&gt;4 SiGe Receiver Array and CMOS Source

In this paper, we report an integrated silicon-based active imaging chipset with a detector array in 0.13 $\mu{\hbox{m}}$ SiGe process and a CMOS-based source array operating in the 240–290 GHz range. The chipset operates at room-temperature with no external RF or optical sources, high-resistivity silicon lenses (HRSi) or waveguides or any custom fabrication options, such as high-resistivity substrates or substrate thinning. The receiver chip consists of a 2-D array of 16 pixels, measuring 2.5 mm $\times$ 2.5 mm with integrated antennas. An electromagnetic-active circuit co-design approach is carried out to ensure high-efficiency interface with detectors operating above cut-off frequencies with good impedance matching, near-optimal noise performance, while simultaneously suppressing the dominant surface-wave modes in a lensless lossy bulk silicon substrate. The array performance is characterized in the WR-3 band between 220–320 GHz. At the designed frequency of 260 GHz, the NEP of all pixels stays between 7.9 ${\hbox{pW}}/\sqrt{\hbox{Hz}}$ –8.8 ${\hbox{pW}}/\sqrt{\hbox{Hz}}$ . The imaging chipset consists of this 2D detector array chip and a CMOS-based source array chip measuring 0.8 mm $\times$ 0.8 mm. The entire system dissipates less than 180 mW of DC power, representing a truly integrated solution.

A new interface used to couple capillary electrophoresis with an inductively coupled plasma mass spectrometry for speciation analysis

In this work, a novel and high-efficiency interface has been developed in coupling CE with inductively coupled plasma MS (ICPMS). The interface completely avoids laminar flow in CE capillary caused by the suction of nebulizer, and can be easily and stably operated at room temperature with high analyte transport efficiency to ICPMS. The new interface has a liquid dead volume smaller than 5 nL, which was much smaller than those (65-2500 microL) reported previously for other interfaces. All above features led to a higher sensitivity and a better electrophoretic resolution for CE-ICPMS coupled with this new interface. With the help of this new interface, we have successfully separated and determined five species of arsenic, As(III), As(V), monomethylarsonic acid, dimethylarsinic acid and p-aminophenylarsonic acid using CE-ICPMS within 11 min with a detection limit of 0.046-0.075 ng/mL and an RSD of 2-6% (n=6).

Hydroquinone as a buffer additive for suppression of bubbles formed by electrochemical oxidation of the CE buffer at the outlet electrode in capillary electrophoresis/electrospray ionization-mass spectrometry.

Hydroquinone was found to suppress bubble formation at the outlet electrode of a sheathless capillary electrophoresis/electrospray ionization-mass spectrometer by replacing the oxidation of water (2H2O(1)<-->O2(g) + 4H+ + 4e) with that of more easily oxidized hydroquinone (hydroquinone<-->p-benzoquinone + 2H+ + 2e). Formation of p-benzoquinone replaces the formation of oxygen gas, effectively suppressing gas bubble formation. Several electrode materials, including platinum, gold-coated stainless steel, and stainless steel wires, were tested. However, hydroquinone suppressed bubbles only at the platinum electrode. Combination of the in-capillary electrode sheathless interface using platinum wire, hydroquinone as a buffer additive, and pressure programming at the inlet of the capillary electrophoresis provided a rugged high efficiency interface for analysis of protein digests using CE/ESI-MS.