The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective ...The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.展开更多
AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 ...AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 patients who underwent mini-PCNL(n = 103) or RIRS n = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.RESULTS Significant differences were found in the hospital stay(9.39 ± 4.01 vs 14.08 ± 5.26, P < 0.0001) and hospitalization costs(2624.5 ± 513.36 vs 3255.2 ± 976.5, P < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group(56.48 ± 24.77) and the mini-PCNL group(60.04 ± 30.38, P = 0.345). The stone-free rates at the first postoperative day(RIRS vs mini-PCNL: 90.2% vs 93.2%, P = 0.822) and the second month postoperatively(RIRS vs mini-PCNL: 93.8% vs 95.1%, P = 0.986) were not significantly different.CONCLUSION RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm.展开更多
The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MES...The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MESDs),with their excellent properties and additional intelligent functions,are considered to be the preferable energy supplies for uninterrupted powering of microsystems.In this review,we aim to provide a comprehensive overview of the background,fundamentals,device configurations,manufacturing processes,and typical applications of MESDs,including their recent advances.Particular attention is paid to advanced device configurations,such as two-dimensional(2D)stacked,2D planar interdigital,2D arbitrary-shaped,three-dimensional planar,and wire-shaped structures,and their corresponding manufacturing strategies,such as printing,scribing,and masking techniques.Additionally,recent developments in MESDs,including microbatteries and microsupercapacitors,as well as microhybrid metal ion capacitors,are systematically summarized.A series of on-chip microsystems,created by integrating functional MESDs,are also highlighted.Finally,the remaining challenges and future research scope on MESDs are discussed.展开更多
Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a n...Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a necessity.We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu^(2+)by exploiting the electroanalytical technique of square wave voltammetry.We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam,which is then electrochemically seeded with gold nanoparticles(Au NPs).The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O.As a result,the heavy metals Pb2+(0.020 mg.L^(-1)detection limit;2.0–16.0 mg.L^(-1)detection range)and Cu^(2+)(0.013 mg.L^(-1)detection limit;0.4–12.8 mg.L^(-1)detection range)can be detected simultaneously with high precision.Furthermore,other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode’s performance,and the recovery rate of groundwater samples varied between 96.3%±2.1%and 109.4%±0.6%.The compactness,flexible shape,low power consumption,and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater,thereby demonstrating the potential to revolutionize the field of environmental monitoring.展开更多
A miniaturized 2.45 GHz permanent magnet electron cyclotron resonance(PMECR) ion source, which has the ability of producing a tens-m A H+beam, has been built and tested at Peking University(PKU). Its plasma chamb...A miniaturized 2.45 GHz permanent magnet electron cyclotron resonance(PMECR) ion source, which has the ability of producing a tens-m A H+beam, has been built and tested at Peking University(PKU). Its plasma chamber dimension is Φ30 mm×40 mm and the whole size of the ion source is Φ180 mm×130 mm. This source has a unique structure with the whole source body embedded into the extraction system. It can be operated in both continuous wave(CW) mode and pulse mode. In the CW mode, more than 20 m A hydrogen ion beam at 40 k V can be obtained with the microwave power of 180 W and about 1 m A hydrogen ion beam is produced with a microwave power of 10 W. In the pulse mode, more than50 m A hydrogen ion beam with a duty factor of 10% can be extracted when the peak microwave power is 1800 W.展开更多
Based on miniaturized components' characteristics, the method of assembling miniaturized gear and shaft together with corresponding calculating model of the interference amount are proposed. On the basis of main effe...Based on miniaturized components' characteristics, the method of assembling miniaturized gear and shaft together with corresponding calculating model of the interference amount are proposed. On the basis of main effecting factors analysis on the gear and shaft assembling interference amount, calculating formula including all factors effective on the interference amount necessary for reliable system running was built up. The methods of reverse calculating theoretical model was used to build up the equivalent simulation model of the theoretical one, together with simulation verification and case study for calculating formula. The results show that the cold assembling method is applicable for miniaturized gear and shaft, but in the assembling process, the interference amount compensating the shape error of contacting surfaces takes a large proportion, which is the main cause of stress variance on contacting surfaces.展开更多
The polypyrrole is the high conductive polymer which was coated onto indium tin oxide (ITO) glass substrate by electroplated technique to fabricate a miniaturized reference electrode.Besides,the morphology of the ITO...The polypyrrole is the high conductive polymer which was coated onto indium tin oxide (ITO) glass substrate by electroplated technique to fabricate a miniaturized reference electrode.Besides,the morphology of the ITO glass reference electrode electroplated with pyrrole has been studied through the instrumental analysis utilizing cyclic voltammetry (CV). Furthermore,the sensing characteristics of the reference electrode have been measured by using commercial instrumental amplifier as the readout circuit.Using the high conductive polymer as miniaturized reference electrode has many advantages such as easy fabrication of coating polymer,without any expensive fabricating equipment,easy carry by the miniaturized technique.Hence,it is suitable for the reference electrode production.展开更多
A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was o...A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed filter exhibits significant improvement in bandwidth compared to the conventional square resonator bandpass filters.展开更多
The major source of morbidity following cardiopulmonary bypass (CPB) is the systemic inflammatory response (SIRS response) which leads to multiple derangements in different organ systems. To combat this, miniaturized ...The major source of morbidity following cardiopulmonary bypass (CPB) is the systemic inflammatory response (SIRS response) which leads to multiple derangements in different organ systems. To combat this, miniaturized cardiopulmonary bypass circuits (MCPBC) have been created to lessen the inflammatory response to CPB. Here we examine early outcomes following coronary artery bypass grafting (CABG) using a MCPBC system compared to conventional bypass techniques at a single institution. Methods: 60 consecutive patients undergoing elective CABG were prospectively enrolled. Nine patients underwent coronary artery bypass grafting (CABG) with conventional CPB (cCABG), 33 underwent off-pump CABG (OPCAB), and the remaining 18 patients underwent CABG with a MCPBC system. Demographics and outcomes were compared between groups and statistical analyses applied. Results: No significant difference was observed in mortality between groups, with only one death reported in total. Morbidity was also low, totaling only 6.7%, with none occurring in the MCPBC group. The MCPBC group required less PRBC and total blood product transfusion than the cCABG and OPCABG groups (p = 0.05), but changes in PLT and Hct over time were not different between groups. Conclusions: The MCPBC system was shown to be comparable to conventional bypass and OPCABG in terms of postoperative complications and mortality. Furthermore, the MCPBC system had the advantage of a decreased transfusion requirement. Based on our preliminary observations, this mini-cardiopulmonary bypass circuit provides a safe alternative to conventional bypass techniques.展开更多
In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure...In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure with a small size of only 1.428 mm*0.5530 mm. The frequency characteristics are simulated and the results show that the 3 dB band width of the proposed filter is about 13.5 GHz from 45.8 GHz to 59.3 GHz. The insertion loss is quite flat through the pass-band and the return loss is relatively low.展开更多
China Asia-Pacific Mobile Telecommunications Satellite Co., Ltd. (China APMT) has signed a QB50 Project Memorandum of Understanding with the Von Karman Institute for Fluid Dynamics (VKI). According to the agreement, C...China Asia-Pacific Mobile Telecommunications Satellite Co., Ltd. (China APMT) has signed a QB50 Project Memorandum of Understanding with the Von Karman Institute for Fluid Dynamics (VKI). According to the agreement, China APMT will launch 50 miniaturized satellites for VKI from 2014-15.展开更多
This paper presents a miniaturized microstrip branch-line coupler with good harmonic suppression performance. The proposed coupler consists of four branch-line sections, each of which is loaded by open-circuit stubs b...This paper presents a miniaturized microstrip branch-line coupler with good harmonic suppression performance. The proposed coupler consists of four branch-line sections, each of which is loaded by open-circuit stubs both at the center and the two ends. This type of loading can realize size reduction and harmonic suppression. As an example, a proposed branch-line coupler operating at 1.0 GHz is designed, fabricated and measured. The results show that the proposed branch-line coupler occupies 67% size of a conventional one and has better than 20 dB suppression from 1.9 to 5.8 GHz. Furthermore, the high slop of the transition band ensures good selectivity of the coupler.展开更多
Miniaturization of Frequency Selective Surface's ( FSS's) size is significant for its application in the limited space. In this paper, a novel methodology for designing low-profile FSS is discussed, and a corr...Miniaturization of Frequency Selective Surface's ( FSS's) size is significant for its application in the limited space. In this paper, a novel methodology for designing low-profile FSS is discussed, and a corresponding multi-layer structure with lumped elements for band-pass response is presented. Based on the equivalent circuit theory,the inductive designed center layer is firstly discussed. Then different numbers of additional capacitive designed layers are added and their performances are presented. Finally,the lumped elements are added both between adjacent layers and between adjacent cells of the additional layers so that the miniaturization performance can be further improved. The simulations for each structure in waves of different polarizations and incident angles are conducted,and the results are presented,which demonstrate the claimed characteristics of the proposed structure.展开更多
An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimen...An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimentally analyzed.The measurement results show that the near-field radiation pattern of the piezoelectric antenna is similar to that of the electric dipole antenna.The radiation efficiency of the piezoelectric antenna is 3-4 orders of magnitude higher than that of electrically small antenna(ESA),with their sizes being the same size,and the maximum transmission distance obtained experimentally is 100 cm,which can be improved by increasing the input power.In addition,the gain,directivity,and quality factor of piezoelectric antenna are also analyzed.In this paper,traditional antenna parameters are creatively used to analyze the performance of piezoelectric antenna.The research conclusions can provide reliable theoretical basis for realizing LF antenna miniaturization.展开更多
This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer (FPI) for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including...This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer (FPI) for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.展开更多
Most of the current analytical methods depend largely on laboratory-based analytical techniques that require expensive and bullky equipment,potentially incur costly testing,and involve lengthy detection processes.With...Most of the current analytical methods depend largely on laboratory-based analytical techniques that require expensive and bullky equipment,potentially incur costly testing,and involve lengthy detection processes.With increasing requirements for point-of-care testing(POCT),more attention has been paid to miniaturized analytical devices.Miniaturized electrochemical(MEC)sensors,including different material-based MEC sensors(such as DNA-,paper-,and screen electrode-based),have been in strong demand in analytical science due to their easy operation,portability,high sensitivity,as well as their short analysis time.They have been applied for the detection of trace amounts of target through measuring changes in electrochemical signal,such as current,voltage,potential,or impedance,due to the oxidation/reduction of chemical/biological molecules with the help of electrodes and electrochemical units.MEC sensors present great potential for the detection of targets including small organic molecules,metal ions,and biomolecules.In recent years,MEC sensors have been broadly applied to POCT in various fields,including health care,food safety,and environmental monitoring,owing to the excellent advantages of electrochemical(EC)technologies.This review summarized the state-of-the-art advancements on various types of MEC sensors and their applications in POCT.Furthermore,the future perspectives,opportunities,and challenges in this field are also discussed.展开更多
The fast separation capability of a novel miniaturized capillary electrophoresis with an amperometric detection (μCE-AD) system was demonstrated by determining clenbuterol and salbutamol in real samples. The effect...The fast separation capability of a novel miniaturized capillary electrophoresis with an amperometric detection (μCE-AD) system was demonstrated by determining clenbuterol and salbutamol in real samples. The effects of several factors such as the acidity and concentration of the running buffer, the separation voltage, the applied potential and the injection time on CE-AD were examined and optimized. Under the optimum conditions, the two β-agonists could be baseline separated within 60 s at a separation voltage of 2 kV in a 90 mmol/L H3BO3-Na2B4O7 running buffer (pH 7.4), which was not interfered by ascorbic acid and uric acid. Highly linear response was obtained for above compounds over three orders of magnitude with detection limits ranging from 1.20×10^-7 to 6.50×10^-8 mol/L (S/N=3). This method was successfully used in the analysis of feed and meat products with relatively simple extraction procedures.展开更多
A simplified compact model for a miniaturized cross-shaped CMOS integrated Hall device is presented. The model has a simple circuit structure,only consisting of a passive network with eight non-linear resistors and fo...A simplified compact model for a miniaturized cross-shaped CMOS integrated Hall device is presented. The model has a simple circuit structure,only consisting of a passive network with eight non-linear resistors and four current-controlled voltage sources.It completely considers the following effects:non-linear conductivity,geometry dependence of sensitivity,temperature drift,lateral diffusion,and junction field effect.The model has been implemented in Verilog-A hardware description language and was successfully performed in a Cadence Spectre simulator.The simulation results are in good accordance with the classic experimental results reported in the literature.展开更多
This study introduced the research and development of a portable and miniaturized system for the measurement of the refractive index of sub-microliter liquid based on a microfluidic chip. A technical method of double-...This study introduced the research and development of a portable and miniaturized system for the measurement of the refractive index of sub-microliter liquid based on a microfluidic chip. A technical method of double-beam interference, was proposed for use in the measurement. Based on this, by using a laser diode as a light source,changes in the refractive index were calculated by utilizing a complementary metal–oxide–semiconductor to detect the movement of interference fringes of the liquid. Firstly, this study simulated the effects of influencing factors on the interference infringes of two Gaussian beams, such as their spot sizes, distance between two beam spots, and detection range. Secondly, this research introduced the system design and construction of the doublebeam interference method and analyzed the results of refractive index tests on sub-microliter aqueous glucose solutions with different concentrations. The measurement accuracy reached 10^(-4) refractive index units. This system has a compact structure and is rendered portable by using batteries for its power supply. The entire system is designed to be a double Z-shaped structure with a length of about 15 cm, a width of 5 cm, and a height of about 10 cm. It can be used to measure changes in the refractive index of sub-microliter to nanoliter liquids based on the use of a microfluidic chip.展开更多
We propose a miniaturized wideband metasurface antenna for 60-GHz antenna-in-package applications.With the glass integrated passive device manufacturing technology,we introduce a coplanar-waveguide-fed(CPW-fed)ring re...We propose a miniaturized wideband metasurface antenna for 60-GHz antenna-in-package applications.With the glass integrated passive device manufacturing technology,we introduce a coplanar-waveguide-fed(CPW-fed)ring resonator to characterize the material properties of the glass substrate.The proposed antenna is designed on a high dielectric constant glass substrate to achieve antenna miniaturization.Because of the existence of gaps between patch units compared with the conventional rectangular patch in the TM10 mode,the radiation aperture of this proposed antenna is reduced.Located right above the center feeding CPW-fed bow-tie slot,the metasurface patch is realized,supporting the TM10 mode and antiphase TM20 mode simultaneously to improve the bandwidth performance.Using a probe-based antenna measurement setup,the antenna prototype is measured,demonstrating a 10-dB impedance bandwidth from 53.3 to 67 GHz.At 60 GHz,the antenna gain measured is about 5 dBi in the boresight direction with a compact radiation aperture of 0.31λ0×0.31λ0 and a thickness of 0.06λ0.展开更多
基金financially supported by the Sichuan Provincial Natural Science Foundation Project under Grant No.2023NSFSC0048.
文摘The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.
基金Supported by the Ningbo Medical Science and Technology Project,No.2014A33
文摘AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 patients who underwent mini-PCNL(n = 103) or RIRS n = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.RESULTS Significant differences were found in the hospital stay(9.39 ± 4.01 vs 14.08 ± 5.26, P < 0.0001) and hospitalization costs(2624.5 ± 513.36 vs 3255.2 ± 976.5, P < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group(56.48 ± 24.77) and the mini-PCNL group(60.04 ± 30.38, P = 0.345). The stone-free rates at the first postoperative day(RIRS vs mini-PCNL: 90.2% vs 93.2%, P = 0.822) and the second month postoperatively(RIRS vs mini-PCNL: 93.8% vs 95.1%, P = 0.986) were not significantly different.CONCLUSION RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm.
基金the financial support from the National Natural Science Foundation of China(Grant Nos.51702095,51722503,51975204)Natural Science Foundation of Hunan Province,China(Grant No.2018JJ3041)+1 种基金the Fundamental Research Funds for the Central Universities(531118010016)Science and Technology Bureau Foundation of Changsha City(kh1904005)。
文摘The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MESDs),with their excellent properties and additional intelligent functions,are considered to be the preferable energy supplies for uninterrupted powering of microsystems.In this review,we aim to provide a comprehensive overview of the background,fundamentals,device configurations,manufacturing processes,and typical applications of MESDs,including their recent advances.Particular attention is paid to advanced device configurations,such as two-dimensional(2D)stacked,2D planar interdigital,2D arbitrary-shaped,three-dimensional planar,and wire-shaped structures,and their corresponding manufacturing strategies,such as printing,scribing,and masking techniques.Additionally,recent developments in MESDs,including microbatteries and microsupercapacitors,as well as microhybrid metal ion capacitors,are systematically summarized.A series of on-chip microsystems,created by integrating functional MESDs,are also highlighted.Finally,the remaining challenges and future research scope on MESDs are discussed.
基金supported by the National Key Research and Development Project of China(2019YFC1804802)。
文摘Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a necessity.We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu^(2+)by exploiting the electroanalytical technique of square wave voltammetry.We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam,which is then electrochemically seeded with gold nanoparticles(Au NPs).The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O.As a result,the heavy metals Pb2+(0.020 mg.L^(-1)detection limit;2.0–16.0 mg.L^(-1)detection range)and Cu^(2+)(0.013 mg.L^(-1)detection limit;0.4–12.8 mg.L^(-1)detection range)can be detected simultaneously with high precision.Furthermore,other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode’s performance,and the recovery rate of groundwater samples varied between 96.3%±2.1%and 109.4%±0.6%.The compactness,flexible shape,low power consumption,and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater,thereby demonstrating the potential to revolutionize the field of environmental monitoring.
基金Project supported by the National Basic Research Program of China(Grant No.2014CB845502)the National Natural Science Foundation of China(Grant No.11575013)
文摘A miniaturized 2.45 GHz permanent magnet electron cyclotron resonance(PMECR) ion source, which has the ability of producing a tens-m A H+beam, has been built and tested at Peking University(PKU). Its plasma chamber dimension is Φ30 mm×40 mm and the whole size of the ion source is Φ180 mm×130 mm. This source has a unique structure with the whole source body embedded into the extraction system. It can be operated in both continuous wave(CW) mode and pulse mode. In the CW mode, more than 20 m A hydrogen ion beam at 40 k V can be obtained with the microwave power of 180 W and about 1 m A hydrogen ion beam is produced with a microwave power of 10 W. In the pulse mode, more than50 m A hydrogen ion beam with a duty factor of 10% can be extracted when the peak microwave power is 1800 W.
基金Sponsored bythe Ministerial Level Advanced Research Foundation (K130306068)
文摘Based on miniaturized components' characteristics, the method of assembling miniaturized gear and shaft together with corresponding calculating model of the interference amount are proposed. On the basis of main effecting factors analysis on the gear and shaft assembling interference amount, calculating formula including all factors effective on the interference amount necessary for reliable system running was built up. The methods of reverse calculating theoretical model was used to build up the equivalent simulation model of the theoretical one, together with simulation verification and case study for calculating formula. The results show that the cold assembling method is applicable for miniaturized gear and shaft, but in the assembling process, the interference amount compensating the shape error of contacting surfaces takes a large proportion, which is the main cause of stress variance on contacting surfaces.
文摘The polypyrrole is the high conductive polymer which was coated onto indium tin oxide (ITO) glass substrate by electroplated technique to fabricate a miniaturized reference electrode.Besides,the morphology of the ITO glass reference electrode electroplated with pyrrole has been studied through the instrumental analysis utilizing cyclic voltammetry (CV). Furthermore,the sensing characteristics of the reference electrode have been measured by using commercial instrumental amplifier as the readout circuit.Using the high conductive polymer as miniaturized reference electrode has many advantages such as easy fabrication of coating polymer,without any expensive fabricating equipment,easy carry by the miniaturized technique.Hence,it is suitable for the reference electrode production.
文摘A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed filter exhibits significant improvement in bandwidth compared to the conventional square resonator bandpass filters.
文摘The major source of morbidity following cardiopulmonary bypass (CPB) is the systemic inflammatory response (SIRS response) which leads to multiple derangements in different organ systems. To combat this, miniaturized cardiopulmonary bypass circuits (MCPBC) have been created to lessen the inflammatory response to CPB. Here we examine early outcomes following coronary artery bypass grafting (CABG) using a MCPBC system compared to conventional bypass techniques at a single institution. Methods: 60 consecutive patients undergoing elective CABG were prospectively enrolled. Nine patients underwent coronary artery bypass grafting (CABG) with conventional CPB (cCABG), 33 underwent off-pump CABG (OPCAB), and the remaining 18 patients underwent CABG with a MCPBC system. Demographics and outcomes were compared between groups and statistical analyses applied. Results: No significant difference was observed in mortality between groups, with only one death reported in total. Morbidity was also low, totaling only 6.7%, with none occurring in the MCPBC group. The MCPBC group required less PRBC and total blood product transfusion than the cCABG and OPCABG groups (p = 0.05), but changes in PLT and Hct over time were not different between groups. Conclusions: The MCPBC system was shown to be comparable to conventional bypass and OPCABG in terms of postoperative complications and mortality. Furthermore, the MCPBC system had the advantage of a decreased transfusion requirement. Based on our preliminary observations, this mini-cardiopulmonary bypass circuit provides a safe alternative to conventional bypass techniques.
文摘In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure with a small size of only 1.428 mm*0.5530 mm. The frequency characteristics are simulated and the results show that the 3 dB band width of the proposed filter is about 13.5 GHz from 45.8 GHz to 59.3 GHz. The insertion loss is quite flat through the pass-band and the return loss is relatively low.
文摘China Asia-Pacific Mobile Telecommunications Satellite Co., Ltd. (China APMT) has signed a QB50 Project Memorandum of Understanding with the Von Karman Institute for Fluid Dynamics (VKI). According to the agreement, China APMT will launch 50 miniaturized satellites for VKI from 2014-15.
基金Supported by the National Natural Science Foundation of China (No. 51007040)
文摘This paper presents a miniaturized microstrip branch-line coupler with good harmonic suppression performance. The proposed coupler consists of four branch-line sections, each of which is loaded by open-circuit stubs both at the center and the two ends. This type of loading can realize size reduction and harmonic suppression. As an example, a proposed branch-line coupler operating at 1.0 GHz is designed, fabricated and measured. The results show that the proposed branch-line coupler occupies 67% size of a conventional one and has better than 20 dB suppression from 1.9 to 5.8 GHz. Furthermore, the high slop of the transition band ensures good selectivity of the coupler.
基金Sponsored by the National Natural Science Foundation of China(Grant No.60801015 and 61001036)the Special Funds Projects for Technological and Innovative Talent of Harbin City(Grant No.2010RFXXG010)+2 种基金the Fundamental Research Funds for the Central Universities(No.HIT.IBRSEM.2009 and HIT.NSRIF.201153)China Postdoctoral Science Foundation(Grant No.LBH-Z10126)Heilongjiang Province Postdoctoral Foundation(Grant No.20110491093)
文摘Miniaturization of Frequency Selective Surface's ( FSS's) size is significant for its application in the limited space. In this paper, a novel methodology for designing low-profile FSS is discussed, and a corresponding multi-layer structure with lumped elements for band-pass response is presented. Based on the equivalent circuit theory,the inductive designed center layer is firstly discussed. Then different numbers of additional capacitive designed layers are added and their performances are presented. Finally,the lumped elements are added both between adjacent layers and between adjacent cells of the additional layers so that the miniaturization performance can be further improved. The simulations for each structure in waves of different polarizations and incident angles are conducted,and the results are presented,which demonstrate the claimed characteristics of the proposed structure.
文摘An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimentally analyzed.The measurement results show that the near-field radiation pattern of the piezoelectric antenna is similar to that of the electric dipole antenna.The radiation efficiency of the piezoelectric antenna is 3-4 orders of magnitude higher than that of electrically small antenna(ESA),with their sizes being the same size,and the maximum transmission distance obtained experimentally is 100 cm,which can be improved by increasing the input power.In addition,the gain,directivity,and quality factor of piezoelectric antenna are also analyzed.In this paper,traditional antenna parameters are creatively used to analyze the performance of piezoelectric antenna.The research conclusions can provide reliable theoretical basis for realizing LF antenna miniaturization.
基金supported by the Key Project of Natural Science Foundation of China under Grant No. 60537040the Natural Science Foundation Project of CQ CSTC under Grant No. 2007BB3125
文摘This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer (FPI) for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.
基金the China National Key R&D Program(No.2017YFC1601604)National Natural Science Foundation of China(NSFC)(No.21777189)for financially supporting this research。
文摘Most of the current analytical methods depend largely on laboratory-based analytical techniques that require expensive and bullky equipment,potentially incur costly testing,and involve lengthy detection processes.With increasing requirements for point-of-care testing(POCT),more attention has been paid to miniaturized analytical devices.Miniaturized electrochemical(MEC)sensors,including different material-based MEC sensors(such as DNA-,paper-,and screen electrode-based),have been in strong demand in analytical science due to their easy operation,portability,high sensitivity,as well as their short analysis time.They have been applied for the detection of trace amounts of target through measuring changes in electrochemical signal,such as current,voltage,potential,or impedance,due to the oxidation/reduction of chemical/biological molecules with the help of electrodes and electrochemical units.MEC sensors present great potential for the detection of targets including small organic molecules,metal ions,and biomolecules.In recent years,MEC sensors have been broadly applied to POCT in various fields,including health care,food safety,and environmental monitoring,owing to the excellent advantages of electrochemical(EC)technologies.This review summarized the state-of-the-art advancements on various types of MEC sensors and their applications in POCT.Furthermore,the future perspectives,opportunities,and challenges in this field are also discussed.
文摘The fast separation capability of a novel miniaturized capillary electrophoresis with an amperometric detection (μCE-AD) system was demonstrated by determining clenbuterol and salbutamol in real samples. The effects of several factors such as the acidity and concentration of the running buffer, the separation voltage, the applied potential and the injection time on CE-AD were examined and optimized. Under the optimum conditions, the two β-agonists could be baseline separated within 60 s at a separation voltage of 2 kV in a 90 mmol/L H3BO3-Na2B4O7 running buffer (pH 7.4), which was not interfered by ascorbic acid and uric acid. Highly linear response was obtained for above compounds over three orders of magnitude with detection limits ranging from 1.20×10^-7 to 6.50×10^-8 mol/L (S/N=3). This method was successfully used in the analysis of feed and meat products with relatively simple extraction procedures.
文摘A simplified compact model for a miniaturized cross-shaped CMOS integrated Hall device is presented. The model has a simple circuit structure,only consisting of a passive network with eight non-linear resistors and four current-controlled voltage sources.It completely considers the following effects:non-linear conductivity,geometry dependence of sensitivity,temperature drift,lateral diffusion,and junction field effect.The model has been implemented in Verilog-A hardware description language and was successfully performed in a Cadence Spectre simulator.The simulation results are in good accordance with the classic experimental results reported in the literature.
基金supported by the National Natural Science Foundation of China(No.61308115)the Natural Science Foundation of Shanghai(No.13ZR1457900)the Shanghai Science and Technology Commission Project(No.15DZ1940400)
文摘This study introduced the research and development of a portable and miniaturized system for the measurement of the refractive index of sub-microliter liquid based on a microfluidic chip. A technical method of double-beam interference, was proposed for use in the measurement. Based on this, by using a laser diode as a light source,changes in the refractive index were calculated by utilizing a complementary metal–oxide–semiconductor to detect the movement of interference fringes of the liquid. Firstly, this study simulated the effects of influencing factors on the interference infringes of two Gaussian beams, such as their spot sizes, distance between two beam spots, and detection range. Secondly, this research introduced the system design and construction of the doublebeam interference method and analyzed the results of refractive index tests on sub-microliter aqueous glucose solutions with different concentrations. The measurement accuracy reached 10^(-4) refractive index units. This system has a compact structure and is rendered portable by using batteries for its power supply. The entire system is designed to be a double Z-shaped structure with a length of about 15 cm, a width of 5 cm, and a height of about 10 cm. It can be used to measure changes in the refractive index of sub-microliter to nanoliter liquids based on the use of a microfluidic chip.
基金supported by the National Key R&D Program of China(Nos.2018YFE0205900 and 2016YFC0800400)the National Science and Technology Major Project,China(No.2018ZX03001008)the National Natural Science Foundation of China(Nos.61306030 and 61674037)。
文摘We propose a miniaturized wideband metasurface antenna for 60-GHz antenna-in-package applications.With the glass integrated passive device manufacturing technology,we introduce a coplanar-waveguide-fed(CPW-fed)ring resonator to characterize the material properties of the glass substrate.The proposed antenna is designed on a high dielectric constant glass substrate to achieve antenna miniaturization.Because of the existence of gaps between patch units compared with the conventional rectangular patch in the TM10 mode,the radiation aperture of this proposed antenna is reduced.Located right above the center feeding CPW-fed bow-tie slot,the metasurface patch is realized,supporting the TM10 mode and antiphase TM20 mode simultaneously to improve the bandwidth performance.Using a probe-based antenna measurement setup,the antenna prototype is measured,demonstrating a 10-dB impedance bandwidth from 53.3 to 67 GHz.At 60 GHz,the antenna gain measured is about 5 dBi in the boresight direction with a compact radiation aperture of 0.31λ0×0.31λ0 and a thickness of 0.06λ0.