Search

Through a novel “Trojan horse” strategy, a reinforced single-atom Co catalyst with robust Co–N4 active sites accommodated in micropore defect-rich carbon nanosheets was rationally fabricated for boosting selective hydrogenation of nitroarenes.

Background Circular RNAs (circRNAs) play vital roles in hepatocellular carcinoma development. However, the role and mechanism of circRNA hsa_circ_0000517 (circ_0000517) in hepatocellular carcinoma development were largely unknown. Methods 45 paired tumor and adjacent nontumor samples were collected from hepatocellular carcinoma patients. The levels of circ_0000517, miR-326 and insulin-like growth factor type 1 receptor (IGF1R) were detected via quantitative reverse transcription polymerase chain reaction or western blot. Cell viability, colony ability, migration, invasion and glycolysis were assessed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, western blot, transwell assay, glucose consumption, lactate production or adenosine triphosphate (ATP) production. The target correlation between miR-326 and circ_0000517 or IGF1R was analyzed via dual-luciferase reporter analysis. The function of circ_0000517 in vivo was assessed via xenograft model. Results circ_0000517 expression was elevated in hepatocellular carcinoma tissues and cell lines. circ_0000517 knockdown suppressed cell viability, colony formation, migration, invasion and glycolysis. miR-326 was sponged via circ_0000517 and miR-326 knockdown reversed the effect of circ_0000517 silence on hepatocellular carcinoma development. miR-326 overexpression inhibited hepatocellular carcinoma development through targeting IGF1R. circ_0000517 knockdown decreased IGF1R expression by modulating miR-326. circ_0000517 downregulation reduced xenograft tumor growth. Conclusion circ_0000517 knockdown repressed hepatocellular carcinoma development in vitro and in vivo by modulating miR-326 and IGF1R.

The long noncoding RNA T cell receptor gamma locus antisense RNA 1 (TRG-AS1) plays an important role in glioblastoma progression. The objective of this study was to determine the expression status of TRG-AS1 in tongue squamous cell carcinoma (TSCC). The regulatory effects of TRG-AS1 depletion on the malignant processes of TSCC cells were illustrated both in vitro and in vivo. Additionally, the precise molecular mechanisms through which TRG-AS promotes TSCC oncogenicity were investigated. TRG-AS1 expression in TSCC tissues and cell lines was detected using reverse transcription-quantitative PCR. Functional experiments including Cell Counting Kit-8 assay, flow cytometric apoptotic assay, migration and invasion assays, and xenograft tumor model analysis were conducted to severally determine the effects of TRG-AS1 on TSCC cell proliferation, apoptosis, migration, and invasion in vitro and tumor growth in vivo. Herein, TRG-AS1 was highly expressed in TSCC and closely associated with advanced TNM stage, high lymph node metastasis, and poor overall survival. Functionally, TRG-AS1 depletion suppressed TSCC cell proliferation, migration, and invasion in vitro; promoted cell apoptosis; and attenuated tumor growth in vivo. Mechanistically, TRG-AS1 served as a molecular sponge for microRNA-543 (miR-543), thereby contributing to the increased expression of Yes-associated protein 1 (YAP1) - a miR-543 target. Rescue experiments confirmed that miR-543 inhibition or YAP1 overexpression abrogated the anticancer effects of TRG-AS1 silencing in TSCC cells. In conclusion, TRG-AS1 aggravates TSCC malignancy by regulating the miR-543/YAP1 axis. Identification of the TRG-AS1/miR-543/YAP1 regulatory pathway may provide novel insights into TSCC diagnosis, prognosis, and therapy.

Visible light-driven photo-Fenton-like technology is a promising advanced oxidation process for water remediation, while the construction of effective synergetic system remains a great challenge. Herein, iron hydroxide oxide (α-FeOOH) with controllable oxygen vacancy defects were engineered on reduced graphene oxide (rGO) nanosheets (named as OVs-FeOOH/rGO) through an in-situ redox method for boosting visible light-driven photo-Fenton-like oxidation. By adjusting the pH environment to modulate the redox reaction kinetics between graphene oxide (GO) and ferrous salt precursors, the oxygen vacancy concentration in α-FeOOH could be precisely controlled. With optimized oxygen vacancy defects obtained at pH 5, the OVs-FeOOH/rGO displayed superior photo-Fenton-like performance for Rhodamine B degradation (99% within 40 mins, rate constant of 0.2278 mg

Oilfield flooding is one of the methods which replenish energy to stratum, improve the recovery factor of oil exploitation in the development of oilfield. The energy consumption of water injection is also part of the totle energy consumption. Oilfield flooding is one of the methods which with the great mass oilfields that in China have entered the later development period, the cost of oil exploitation is rising, and the water injection in the same way. It is an effective way to reduce the cost of water injection by using computer technology to optimize operation control of oil field water injection system. Water injection system analyzed in this paper is suitable by combining multiple centrifugal pump and frequency converter in the composition of water injection station as the water system, optimization mathematical model is established for water injection system, using c++ optimization software is compiled, selects the improved constrained variable dimension method was used to solve the model, the optimization result is applied to a production plant of daqing oilfield water injection system. After adopting the optimized pumping measures, the system efficiency is increased by 1.8% when meeting the water injection requirements, and the operation cost is saved by about 10,000 RMB per day, which reduces the production cost of the oilfield.

Through Silicon Via (TSV) technology is capable meeting effective, compact, high density, high integration, and high-performance requirements. In high-frequency applications, with the rapid development of 5G and millimeter-wave radar, the TSV interposer will become a competitive choice for radio frequency system-in-package (RF SIP) substrates. This paper presents a redundant TSV interconnect design for high resistivity Si interposers for millimeter-wave applications. To verify its feasibility, a set of test structures capable of working at millimeter waves are designed, which are composed of three pieces of CPW (coplanar waveguide) lines connected by single TSV, dual redundant TSV, and quad redundant TSV interconnects. First, HFSS software is used for modeling and simulation, then, a modified equivalent circuit model is established to analysis the effect of the redundant TSVs on the high-frequency transmission performance to solidify the HFSS based simulation. At the same time, a failure simulation was carried out and results prove that redundant TSV can still work normally at 44 GHz frequency when failure occurs. Using the developed TSV process, the sample is then fabricated and tested. Using L-2L de-embedding method to extract S-parameters of the TSV interconnection. The insertion loss of dual and quad redundant TSVs are 0.19 dB and 0.46 dB at 40 GHz, respectively.

In this paper, we design and fabricate a radio frequency (RF) signal transmission structure for a 3D stacked structure. Usually, this structure uses co-planar waveguide (CPW) and Through Silicon Via (TSV) to realize the horizontal and vertical RF signal transmission on the same interposer respectively. With the help of micro-bump, we can transport RF signal in a stacked structure. Furtherly, we design and fabricate a patch antenna with a stacked structure, fed by the structure we proposed. Through the measurement of the antenna, we determine the effectiveness of this transmission structure.

In recent years, radio frequency (RF) systems have been moving towards miniaturization. Traditional wire-bonding technology used in RF systems have significant disadvantages in terms of parametric inductance and package size scaling-down. Therefore, people pay more attention to the high-performance and small-size interconnection schemes of RF systems. In this regard, we designed a series of micro bumps arrays for RF application, including arrays with diameters of 15 μm / 30 μm / 40 μm and a pitch of 30 μm / 60 μm / 80 μm. To study RF property of micro bumps array, Cu / Sn micro bumps arrays jointed double-layer coplanar waveguide (CPW) structures were prepared and tested. By subtracting the insertion loss of CPW line from the test structure's insertion loss, the insertion loss of the micro bumps array can be obtained. Comparing the insertion loss of micro bumps arrays with different diameters, the insertion loss of the micro-bumps array with a diameter of 15 μm is the smallest, and the micro bumps with multiple rows have lower insertion loss than a single micro bump. Among them, the insertion loss of a 3 × 6 micro bumps array with a diameter of 15 μm after bonding is 0.15 dB@40GHz.

This paper proposes a vertical coaxial transmission structure made of a centered Cu TSV surrounded with a cycle of TSVs as grounding shield. To verify the feasibility, a set of vertical coaxial transmission structure linked with CPW lines is designed to be able to work at 40GHz and parametric study is conducted in the meantime. By changing the diameter of the grounded TSV ring array and the space of centered RF TSVs, the results show that test structures have good high frequency transmission performance; the larger the diameter of the grounded TSV ring array, the better the transmission performance; the S21 parameter does not change significantly when the space between the two centered RF TSVs is changed. With developed TSV process, sample is fabricated and tested. The insertion loss is less than 1.2dB@40 GHz for the two vertical coaxial transmissions structures linked with CPW lines, and it can be derived that it has a less than 0.15dB@40GHz for a single coaxial transmissions structure.

The long noncoding RNA T cell receptor gamma locus antisense RNA 1 (TRG-AS1) plays an important role in glioblastoma progression. The objective of this study was to determine the expression status of TRG-AS1 in tongue squamous cell carcinoma (TSCC). The regulatory effects of TRG-AS1 depletion on the malignant processes of TSCC cells were illustrated both

In this study, we present a Q-band patch antenna with an underling cavity integrated on the stacked high-resistivity Si interposers. A process is developed and sample is fabricated. Evaluation is done and the measurement results shows that it has an operating frequency of 32.75GHz, a –10dB bandwidth of 1.04GHz, a maximum gain of 3dB. Those results prove the feasibility of integrating high-frequency antennas with TSV interposer preliminary.

This paper proposed a three-dimensional integrated RF transceiver module based on high resistivity Si interposer embedded with microchannel for on-site heat dissipation. It's composed of three stacked layers of TSV interposer, including the bottom one embedded with microchannels for on-site cooling which has four high power chips assembled on its top side, the middle one having four large cavities to accommodate the chips assembled on the bottom one which is utilized as a supporting layer, the top one having a IC driver chip mounted on its top side. In order to study its thermal property, a simplified thermal resistance network is built and analysis is done. To validate this method, finite element simulation is conducted and the results show that maximum deviation of the temperature rise of each high power chip mounted on the bottom Si interposer referring to coolant is 9.04% and minimum deviation is 4.85% in the range from 0.1m/s to 1m/s for DI coolant.

TSV technology enables small size, high density, high integration, and high performance 3D integration. Currently, its application or even commercialization is occurring in Memory IC, high performance logic IC, and MEMS, microwave and millimeter wafer application will become an emerging field in coming years with booming of the 5G, millimeter wave radar. For high frequency application, TSV interposer based 2.5D/3D integration is a competitive choice. This paper proposes a dual redundant TSV interconnection design in High resistivity Si interposer for Millimeter Wave Applications. To verify the feasibility of this design, a set of test structures that can work at millimeter wave is designed, which is made of dual redundant TSV interconnection linked CPW lines. Process is developed for High resistivity Si TSV interposer and Test structures are fabricated and tested, the results show that the insertion loss of the test structure with dual redundant TSV interconnect is

For cooling the 2.5D integrated high power IC device, this paper present a TSV interposer embedded parallel linear microchannels, demonstrate its assembly and thermal property evaluation. The sample is about 9.45 mm  9.5 mm in size, with liner microchannel 100 μm/100 μm in the width/space, 300 μm in the depth, a symmetric flow guiding structure arranged in inlet/outlet region. TSV interposer embedded microchannel is fabricated with DRIE process and Si-Si direct bonding process. For thermal property evaluation, a customized high power IC chip with on site temperature sensor is integrated on the TSV interposer and wired by PCB board. According to the current test results, when the equivalent thermal flux input density is risen to 283 w/cm2, a total thermal input about 66.55 W, the DI wafer is set at a flow rate of 100 ml/min, the temperature rise to 95.1°C, and the pressure drop is 40 Kpa, which is preliminarily verified that it has a good cooling capability.

In this paper, we present a TSV interposer integrated X-band microstrip filter. It designed as working at X band with an insertion loss (IL) of 2.2dB, measuring 2.8mm×3.7mm in size. With processed sample, the measured bandwidth (BW) is about 2.33GHz, the passband insertion loss is about 2.2dB.

Establishing the pipeline network model of oilfield water injection under known partial pressure through fuzzy clustering method. In order to solve the inversion of pipe element friction coefficient in the case that the joint pressure of water injection pipe network is partly known, the simulation mathematical model of network node pressure and the optimal mathematical model of pipe element friction coefficient inversion are established respectively. By combining the simulation of nodal pressure by quasi-newton method and the inversion of friction coefficient by particle swarm optimization, the ideal pipe element friction coefficient of the pipe network with the partly unknown part of the node pressure can be inverted to achieve the partial accurate solution and partial estimation solution of the pipe element friction coefficient.

Transmitter/Receiver (T/R) is a basic part for the RF front-end module, whose miniaturization and integration are very important for the improvement in integration density, function complexity and performance. The state of art of high performance T/R is mainly realized with heterogeneous integration based on advance ceramics such as High Temperature Co-fired Ceramic (HTCC) and Low Temperature Co-fired Ceramic (LTCC). This scheme is helpful to fully utilize the excellent performance of various devices based on substrate such as GaAs, InP, and GaN substrate, however, it confronts shortcomings in re-wiring lines of low precision, shrinkage mismatch during co-firing process, low thermal conductivity. TSV interposer having its Re-wiring line realized with IC back-end metallization process, MEMS process, etc., and using Through-Silicon-Via (TSV) to achieve vertical interconnections between rewiring lines on both surface, is able to provide a good match in rewiring line with RF microelectronic chips, factoring in improvement in RF loss properties with high-resistivity Si as substrate instead of normal low resistivity Si, therefore is acknowledged to be a competitive package substrate for building a highly integrated RF system. In this context, we present a 2.5D integrated L-band Receiver based on TSV interposer, the test results prove the feasibility of 2.5D RF integration enabled by high-resistivity Si interposer.

In this paper, a TSV interposer embedded with microchannel is proposed for 2.5D integration of GaN RF power device. S-shaped microchannel with symmetrical radial diversion structure in inlet/outlet region is designed to make a balance among process, cooling property and flow resistance. In order to avoid issues regarding to fabrication of TSV interconnections on thick bonded Si wafer embedded with microchannels, TSV is designed as having three different diameters along its axis which are 100mm, 180mm and 220mm in sequence from the bottom end to the top end and total height of 500mm. A process is developed with Si-Si wafer bonding process for the proposed TSV interposer embedded with S-shaped microchannel that is 50mm/100mm in its width/pitch, 300mm in the depth. Sample of TSV interposer embedded with microchannel is fabricated and tested electrically, it has a tested resistance about 6mW for TSV interconnection. In order to validate the proposed TSV interposer, A GaN RF power amplifier chip which has an equivalent thermal flux about 400W/cm2 is utilized as test vehicle and 2.5D integrated GaN RF power amplifier based TSV interposer with embedded cooling microfluidics is designed, assembled and tested. The experimental result show that 2.5D integrated GaN Power amplifier can work correctly.

As Through Silicon Vias (TSV) based System In a Package (SIP) technology is booming, high quality integrated inductor is desired for Radio Frequency (RF) application. Due to the substrate loss, traditional TSV interposer integrated inductor confronts low quality factor (Q) issues. In this study, we present a TSV interposer integrated suspended spiral inductor to address the substrate loss issues. To testify this concept, a process is designed, which is featuring in a releasing process by a combination of Si Deep Reactive Ion Etching (DRIE) and Reactive Ion Etching (RIE) process to achieve TSV interposer integrated suspended inductor. Based on the process, two inductors which are used as test vehicles are designed fabricated and tested. A releasing gap of 40mm is achieved for the samples. One inductor has an inductance of 2nH and a quality factor of 20 at 20GHz, another has an inductance of 5nH and a quality factor of 9 at 5GHz, which are about one times improvement in quality factor and about two times improvement in working bandwidth compared with the referring inductor designs of similar structure but without substrate releasing.

In this paper, TSV interposer integrated 3D high density capacitor is presented, which is featuring in a Metal-Insulation-Metal (MIM) structure on inside surface of blind TSVs array. A process is developed with Al2O3 as insulation layer deposited by Atomic Layer Deposition (ALD). With this process, TSV interposer integrated high density 3D capacitor sample is fabricated, and characterized in terms of capacitance density, leakage current, breakdown voltage, Self-resonant frequency (SRF) and Equivalent series Resistance (ESR). According to the experiment, it has a capacitance density of 5nF/mm2, a leakage current less than 2.5mA at a bias voltage below 10V and a breakdown voltage about 20V, a predicted ESR about W and a ESR about MHz. The reason is investigated with simulation results and optimization direction is assured.

In this paper, the technology of through silicon via (TSV) is applied to radio frequency (RF) receiver module. A grounded coplanar waveguide (GCPW) with TSV is proposed, through the simulation, and the improvement of TSV on RF transmission performance is studied, including TSV's aperture size, density, arrangement and so on. This paper also studies basic components model such as resistance, capacitance and inductance on the TSV motherboard. Then, an S-band dual-channel receiver module based on the technology of TSV is presented. Sixteen chips are integrated in the receiver module such as amplifier chips, power splitter chips, phase shifter chips and attenuator chips. The size of the final receiver module we proposed is 25mm×18mm×1.5mm, which is 2.5% of traditional RF receiver module, and the package is 8g, which is also 2.5% of the traditional RF receiver module.

In this paper a highly integrated MCP concept apply to MMICs from DC up to Ku-band is presented. This type of package of low-temperature co-fired ceramic system-in-package (LTCC-SIP) with ball grid array (BGA) structures hereby can realize miniaturization, low-weight and multifunction. More than one of the multi-function MMICs are wire-bonding or flip-chip mount on the top of multilayer LTCC substrate which was integrated all kinds of passive functions such as filter, resistance, capacitance, and the SIP can be surface mount on a PCB serving as motherboard through the via and BGA on the bottom side. The simulation and measurement for this package of the return loss return loss were −12dB at 18GHz that can meet the need of most of RF performance. And the size of the final package of the single channel RF LTCC-SIP we processed is 55mm × 20mm × 4.5mm, which is 1.4% of traditional RF module, and the package is 10g in weight, which is also 1.4% of the tradition RF module.

The bulk titanium deep reactive ion etching (DRIE) enabled high aspect ratio structures and devices are promising for harsh and in vivo environments applications. An etching model is necessary for better profile control to acquire needed performance, in which a correct ion angular distribution (IAD) in chlorine plasma is crucial. In this paper, an overhang SU-8 structure is proposed to experimentally in-situ measure the IAD by analyzing the etching profiles. With these data, a profile evolution model is developed to predict the titanium DRIE process.

Molybdenum is a promising material for bulk MEMS applications for its high melting point, radiation resistance, high strength and conductivity. This paper reports on the development of wafer level bulk molybdenum ICP etching. Various etching chemistry are explored. The influence of process parameters (coil power/ICP power, platen power/RIE power and gas flow rate) on the etching rate, selectivity to SU-8 mask and etching profile anisotropy are investigated. With an optimized recipe, an etching rate of 2.63μm/min has been achieved with a profile of 70° and samples are employed as electrodes in micro Electrical Discharge Machining (μEDM).

In this study, a sandwiched titanium-on-glass (TOG) substrate was used to fabricate laterally driven microelectromechanical systems devices with bulk titanium as the structural material. 4'' TOG wafers with a titanium device layer of 25 µm were fabricated by low temperature SU-8 wafer bonding and chemical mechanical polishing. By using inductively coupled plasma for titanium deep etching as well as dry release, suspended high-aspect-ratio bulk titanium structures were realized with only one mask. A laterally driven electrostatic comb-driven bulk titanium resonator was manufactured as a preliminary demonstration. The resonator achieves a quality factor of 110 at 34 kHz, and survived 10 000 g shock without damage. Due to the high mechanical endurance and excellent corrosion resistance of titanium, TOG technology may open up many new applications in harsh environments.