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Coated cutting tools are widely used in the manufacturing industry due to their excellent properties of high heat resistance, high hardness, and low friction. However, the milling process is a dynamic process, so the coatings of milling tools suffer severe cyclic impact loads. Impact resistance is important for the life of milling tools. Multi-coatings with different layer thickness may influence their impact resistance, but few studies focus on this topic. In this study, CVD coating with a structure of TiN layer, Al2O3 layer, and TiCN layer was selected as the research objective. Four different CVD coatings with different layer thicknesses were designed and prepared. The impact resistance test method was proposed to simulate the impact due to cut-in during down the milling process. We obtained the load by setting an impact depth of 25/30/35 µm, recording the impact force during the impact process, and calculating the contact stress; it was found that, at the impact depth of 25/30/35 µm, the download loads were around 9/11/13 N, while the contact stresses were all around 1 GPa. The failure morphology of the coating surface was investigated after the impact process. By comparing the contact stress and the surface morphology of the designed coatings, the impact resistance of four kinds of designed CVD coatings were evaluated. Experiments have shown that an increase in coating thickness and total coating thickness reduces impact resistance by about 10%. The impact resistance of coating samples without a TiN surface layer also decreased by about 10%. When the surface layer of TiN was thinner than 1 µm, the surface layer of TiN was prone to chipping and peeling off. Decreasing the thickness of the middle layer of Al2O3 and increasing the thickness of the inner layer of TiCN obviously lowered the impact resistance.

Acid stress is a challenging condition that yeast cells must overcome during fermentation. Enhancing the inherent tolerance of industrial Saccharomyces cerevisiae to organic acid stresses is crucial for increasing fermentation efficiency and reducing economic costs. In a previous study, we constructed a Saccharomyces cerevisiae strain SWY85S with improved tolerance to citric acid stress by modifying the second PEP4-allele. Malic acid is a dominant organic acid in grapefruit, which forms the acidic constituents of wine fermentation mash and finished products. We investigated the malic acid stress tolerance of the strain SWY85S in comparison with that of a strain with one PEP4-allele disrupted and the wild-type strain in this study. Our results revealed that the strain SWY85S demonstrated greater tolerance of malic acid stress, regardless of whether it was cultured with adequate nutrient supplies or under amino acid starvation. Moreover, the strain SWY85S performed remarkably in converting glucose to ethanol during fermentation under malic acid stress. This study provides insights into the role of a vacuolar PEP4-allele coding product in response to environmental stress and the physiological mechanism of yeast to withstand organic acid stress.

Even though lithium-sulfur (Li-S) batteries have made much progress in terms of the delivered specific capacity and cycling stability by the encapsulation of sulfur within conductive carbon matrixes or polar materials, challenges such as low active sulfur utilization and unacceptable Coulombic efficiency are still hindering their commercial use. Herein, a lithium-rich conjugated sulfur-incorporated, polymeric material based on poly(Li2S6-r-1,3-diisopropenylbenzene) (DIB) is developed as a cathode material for high rate and stable Li-S batteries. Motivated by extra Li+ ions affording fast Li+ redox kinetics across the conjugated aromatic backbones, the Li-rich sulfur-based copolymer exhibits high delivery capacities (934 mAh g-1 at 120 cycles), impressive rate capabilities (727 mAh g-1 even under a current of 2 A g-1), and long electrochemical cycling performance over 500 cycles. Moreover, by use of the elastic nature and thermoplastic properties of the sulfur-incorporated, polymeric material, a prototype of a flexible Li-S pouch cell is constructed by using a poly(Li2S6-r-DIB) copolymer cathode and paired with the flexible carbon cloth/Si/Li anode, which exhibits stable electrochemical performance (658 mAh g-1 after 100 cycles) and operational capability even under folding at various angle (30°, 60°, 90°, 120°, 150°, 180°). This work extends the molecular-design approach to obtaining a high-performance organosulfur cathode material by introducing extra Li+ ions to promote redox kinetics, which provides valuable guidance for the development of high-performance Li-S batteries for practical applications.

Connexins are membrane expressed proteins, which could assemble into hexamers to transfer metabolites and secondary messengers. However, its roles in pancreatic cancer metastasis remains unknown. In this study, by comparing the gene expression patterns in primary pancreatic cancer patients primary and liver metastasis specimens, we found that Gap Junction Protein Beta 3 (GJB3) significantly increased in Pancreatic ductal adenocarcinoma (PDAC) liver metastasis. Animal experiments verified that GJB3 depletion suppressed the hepatic metastasis of PDAC cancer cells. Further, GJB3 over expression increased the neutrophil infiltration. Mechanistic study revealed that GJB3 form channels between PDAC tumor cells and accumulated neutrophil, which transfer cyclic adenosine monophosphate (cAMP) from cancer to neutrophil cells, which supports the survival and polarization. Taken together, our data suggesting that GJB3 could act as a potential therapeutic target of PDAC liver metastasis.

Considering the complexity and uncertainty of decision-making in the operating environment of an unmanned underwater vehicle (UUV), this study proposes an autonomous decision-making method based on the dynamic influence diagram (DID) and expected utility theory. First, a threat assessment model is established for situation awareness of the UUV. Accordingly, a DID model is developed for autonomous decision-making of the UUV. Then, based on the threat assessment results for the UUV, the utility of each decision-making plan in the decision-making nodes is inferred and predicted. Subsequently, the principle of maximum expected utility is used to select an optimal autonomous decision-making plan. Finally, the effectiveness of the DID method is verified by simulation. Compared with the traditional expert systems, the DID system shows great adaptability and exhibits better solutions of dynamic decision problems under uncertainty.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy driven by genetic mutations and/or epigenetic dysregulation. Gemcitabine chemotherapy is the first-line regimen for pancreatic cancer but has limited efficacy. Our previous study revealed the role of SETD2-H3K36me3 loss in the initiation and metastasis of PDAC, but little is known about its role in tumor metabolism. Here, we found that SETD2-deficient PDAC enhanced glycolysis addiction via upregulation of glucose transporter 1 (GLUT1) to meet its large demand for glucose in progression. Moreover, SETD2 deficiency impaired nucleoside synthesis by directly downregulating the transcriptional level of transketolase (TKT) in the pentose phosphate pathway. The metabolic changes confer SETD2-deficient PDAC cells with increased sensitivity to gemcitabine under glycolysis restriction conditions. Collectively, our study provides mechanistic insights into how SETD2 deficiency reprograms glycolytic metabolism to compensate for insufficient nucleoside synthesis, suggesting that glycolysis restriction combined with gemcitabine might be a potential therapeutic strategy for PDAC patients with SETD2 deficiency.

This study investigated the specific molecular mechanism and the roles of extracellular matrix protein Spondin 1 (SPON1) in the development of pancreatic ductal adenocarcinoma (PDAC).The expression pattern and clinical relevance of SPON1 was determined in GEO, Ren Ji and TCGA datasets, further validated by immunohistochemical staining and Kaplan-Meier analysis. Loss and gain of function experiments were employed to investigate the cellular function of SPON1 in vitro. Gene set enrichment analysis, luciferase assay, immunofluorescence and Western blot and immunoprecipitation were applied to reveal the underlying molecular mechanisms. Subcutaneous xenograft model was used to test the role of SPON1 in tumour growth and maintenance in vivo.SPON1 is significantly upregulated in PDAC tumour tissues and correlated with progression of PDAC. Loss and gain of function experiments showed that SPON1 promotes the growth and colony formation ability of pancreatic cancer cells. Combining bioinformatics assays and experimental signalling evidences, we found that SPON1 can enhance the IL-6/JAK/STAT3 signalling. Mechanistically, SPON1 exerts its oncogenic roles in pancreatic cancer by maintaining IL-6R trans-signalling through stabilizing the interaction of soluble IL-6R (sIL-6R) and glycoprotein-130 (gp130) in PDAC cells. Furthermore, SPON1 depletion greatly reduced the tumour burden, exerted positive effect with gemcitabine, prolonging PDAC mice overall survival.Our data indicate that SPON1 expression is dramatically increased in PDAC and that SPON1 promotes tumorigenicity by activating the sIL-6R/gp130/STAT3 axis. Collectively, our current work suggests SPON1 may be a potential therapy target for PDAC patient.

When unmanned underwater vehicles (UUVs) perform tasks, the marine environment situation information perceived by their sensors is insufficient and cannot be shared; moreover, the reasoning efficiency of the situation information is not high. To deal with these problems, this paper proposes an ontology-based situation awareness information expression method, using the Bayesian network method to reason about situation information. First, the situation awareness information is determined in uncertain events when performing tasks in the marine environment. The core and application ontologies of UUV situation awareness are also established. Subsequently, semantic rules are constructed, and uncertain events are identified through the corresponding semantic rules. The Jess inference engine is used to update the ontology model. Because the ontology cannot reason about uncertainty, it is transformed into the Bayesian network to reason about the impacts of uncertain events on tasks. Simulation experiments verify the effectiveness and accuracy of the situation awareness reasoning method that combines the ontology and the Bayesian network.

Lithium-sulfur (Li–S) batteries are considered to be a promising energy storage owing to high energy density and low cost. However, the S cathodes are still suffering from poor cycle life and low Coulombic efficiency due to ‘shuttle effect’ of lithium polysulfide. Herein, we report a novel and effective strategy to fabricate a free-standing Li–S battery cathode with enriched anchoring and catalytic N-sites host. Benefiting from synergistic effects of multifunctional porous carbon nanofiber host (g-C3N4@PCNF), the g-C3N4@PCNF/S cathode achieves good flexibility and excellent cycling retention, such as stable long cycle performance with a capacity decay of only 0.056% per cycle over 500 cycles at 1.0 A g−1. The excellent performance of g-C3N4@PCNF/S cathode can be mainly attributed to: (i) the interconnected network and internal porous structure of PCNF offering free space for S-loading and volume change during charge/discharge; (ii) the 3D g-C3N4@PCNF host providing an efficient electron/Li+ transport highway for fast interfacial reaction kinetics; (iii) the catalytic effect of g-C3N4 promoting rapid redox conversion of S species and retarding polysulfide shuttling. This effective strategy has demonstrated great potential as good candidates for commercial flexible and durable Li–S batteries.

In order to solve the problem of insufficient search ability of the unmanned surface vehicle (USV) collision avoidance planning algorithm, this paper proposes an improved ant colony optimization algorithm (ACO). First, aiming at the static unknown environment, in order to improve the real-time performance of USV online planning, and considering the environmental characteristics of USV operation for improving ACO to search for the optimal path, a dynamic viewable method is proposed for the local environment model. Second, according to the known dynamic environment, based on the motion velocity model and International Regulations for Preventing Collisions at Sea (COLREGS), a reverse eccentric expansion method is designed to deal with the dynamic obstacles. Then, aiming at the problem that ACO has a slow convergence speed, an improved pseudo-random proportional rule is proposed to select the ant state transition. And the wolf pack allocation principle and the maximum-minimum ant system are used to update the global pheromone to avoid the search falling into local optimum. Finally, the convergence, real-time performance, and stability of the improved ACO are verified through the simulation experiment of USV collision avoidance in the static unknown and dynamic known environment.

The unmanned underwater vehicle (UUV) plays an ever increasing and important role in the modern marine environment. In particular, the tasks of underwater reconnaissance and surveillance, underwater mine hunting and anti-submarine warfare, all poses a serious and dangerous threat to humans. UUV has become the fore-running technology to accomplish such missions. In this paper, a method based on dynamic Bayesian network modeling was proposed to evaluate the UUV in an underwater threat situation. We divided the UUV threats into three categories: environmental factors, platform factors, and mission factors. Through each of these categories, we carried out factor extraction and set up the priori probability according to the characteristics. Setting up the static Bayesian network involved the addition of state transition probability and establishment of the model for assessing the dynamic Bayesian threat situation. By comparing the results of the static and dynamic Bayesian simulation, it was shown that the dynamic Bayesian is superior. Moreover, by analyzing the sensitivity, we recognized the greatest current threat and in response, determined the appropriate UUV countermeasures. The results showed that the dynamic Bayesian method has great practical significance and value for threat assessment.

Stroke is a cerebrovascular disease that results in decreased blood flow. Although Panax notoginseng (PN), a Chinese herbal medicine, has been proven to promote stroke recovery, its molecular mechanism remains unclear. In this study, middle cerebral artery occlusion (MCAO) was induced in rats with thrombi generated by thread and subsequently treated with PN. After that, staining with 2,3,5-triphenyltetrazolium chloride was employed to evaluate the infarcted area, and electron microscopy was used to assess ultrastructural changes of the neurovascular unit. RNA-Seq was performed to determine the differential expressed genes (DEGs) which were then verified by qPCR. In total, 817 DEGs were identified to be related to the therapeutic effect of PN on stroke recovery. Further analysis by Gene Oncology analysis and Kyoto Encyclopedia of Genes and Genomes revealed that most of these genes were involved in the biological function of nerves and blood vessels through the regulation of neuroactive live receptor interactions of PI3K-Akt, Rap1, cAMP, and cGMP-PKG signaling, which included in the 18 pathways identified in our research, of which, 9 were reported firstly that related to PN’s neuroprotective effect. This research sheds light on the potential molecular mechanisms underlying the effects of PN on stroke recovery.

Continuous space heating is generally adopted for buildings in cold regions of northern China. The energy consumption for space heating is very large. Since office buildings are usually not occupied during nights, intermittent space heating could be used to shorten the heating time and save energy. This present paper studies how much energy could be saved and which factors affect the energy-saving compared to continuous heating. This paper selects a typical room in an office building, adopts room heat balance method, and establishes the dynamic thermal model of the room, and studies the dynamic thermal characteristics and energy-saving rate of intermittent heating. The conclusions are as follows: (1) Compared to continuous heating, the energy-saving rate of intermittent heating is 17.9% when the preheating period is 1 h for this case. (2) The energy-saving rate reduces with the increase of preheating period. When the preheating period is 4 h, the energy-saving rate is 10.7%. The preheating period should be less than 2 h for this case.

Sodium-ion batteries (SIBs) are considered to be promising alternatives to lithium-ion batteries (LIBs) due to the greater natural abundance of sodium raw materials versus lithium raw materials. However, to date, the plating and stripping mechanism of Na metal in full SIBs, which is one of the functional reactions in SIBs, has yet to be clarified. Herein, we systematically investigate the influence of current density on the nature of Na-metal deposition in a full-cell SIB using a three-electrode system composed of a commercial NaNi1/3Fe1/3Mn1/3O2 (NFM) cathode, a hard carbon (HC) anode, and a Na-metal reference electrode. Using electrochemical methods and ex situ electron microscopy, it is found that the deposition of Na metal increases with increasing current and plates on the HC anode in a spherical shape; the above morphology is in contrast to the dendrite-like morphology of Li plated onto graphite. Using first-principles calculations, it is discovered that the suppression of dendrite growth on SIB anodes can be attributed to the homogeneous adsorption energy of Na atoms on different facets of a sodium crystal.

Considering the UUV energy self-contained is limited, and the task to execute has different importance, how to make UUV in the finite energy configuration case as far as possible to complete the important task with high priority, the path planning problem for multi constrained multi-objective is one of the key problems of autonomous control technology for UUV to solve. A hybrid optimization algorithm based on artificial fish swarm algorithm and ant colony algorithm was proposed, using the weight coefficient method change multi-objective problem into single objective; for limited energy value, use the methods of iteration and decreasing of operating points. The simulation results show that the new algorithm is valid.

Underwater unmanned detector has been the crux to the exploration and exploitation of marine resources. With the development of undersea vehicles especially Autonomous Underwater Vehicle, higher and higher petitions of intelligent control and autonomous navigation are asked. The autonomous planning of AUV consists of two parts: one is the global path planning on the basis of the known environmental information; the other is the local planning for obstacle avoidance based on sensor data. This paper presents a QPSO algorithm with particle's taxonomic evolution, and designs AUV autonomous planning simulation software on the basis of QT development platform. For the known environment, we establish the annular space optimization model, adjust the velocity and heading of AUV to avoid obstacle by optimization algorithm. A method of the local planning for obstacle avoidance is proposed based on sensor detection window for unknown obstacles. The effectiveness of the proposed method is demonstrated by simulation.

A method for multi-mode stability analysis of power amplifier is presented which does not demand strict circuit symmetry. Transformation from n-port signals to n-mode signals is used to provide the oscillating signal's “mode” information which allows the circuit designer to find the instability source and to adopt suitable methods for circuit stabilization. The proposed method has been applied to a four-branch combining power amplifier circuit to verify its effectiveness.

A novel method of full phase-coherent synthesis is proposed in this paper, which uses the frequency-converting technology and the phase-locked loop to fulfill the transmission and tracking of the frequency and phase between the main loop and secondary loops. This method, which differs from the traditional converting-filtering scheme, can solve the tradeoff between the frequency difference and the bandwidth of the full phase-coherent outputs, and it can have a high isolation between the outputs. A Ka-band full phase-coherent frequency synthesizer is implemented based on the idea. The measured results show that this novel full phase-coherent frequency synthesis method proposed in this paper is correct. The frequency synthesizer has full phase-coherent characteristics along with a very low phase noise, fast hopping time, high spurious rejection, and very high isolation between the main output and the secondary output.

This paper presents an X-band high gain and high power three-stage PHEMT monolithic microwave integrated circuit (MMIC) power amplifier (PA). Based on 0.15-μm GaAs power PHEMT technology, this PA is fabricated on a 2-mil thick wafer. While operating under 7.2 V and 3300 mA dc bias condition, the characteristics of 29.2-dB small signal gain, 11.7-W output power, and 42.2% power added efficiency at 9.2 GHz can be achieved.

This letter presents a broadband monolithically integrated waveguide transition module designed for operating around 300 GHz. This transition module employs waveguide WR2.8 and utilizes dipole-based transitions from waveguide to CPWG. The dipole-based transition is designed and fabricated using InP terahertz monolithic integrated circuit (TMIC) technology, so as to be directly integrated monolithically on the TMIC chip, e.g. amplifier, instead of using bond-wires. The measured results show that the insertion loss of this transition is less than 1.5 dB from 285 to 309 GHz, and return loss is better than −9 dB in the whole operation frequency band (270-330 GHz). Moreover, the dipole-based transition has a compact size that is suitable for minimal assembly.

This paper demonstrates an active single-balanced mixer with InP double heterojunction bipolar transistor (DHBT) process for direct down-conversion system at 89 GHz. Authors use Coplanar Waveguide (CPW) as on-chip transmission line and tune an on-chip CPW balun to allocate LO signal to the switch cell. Benefiting from its balanced structure, this mixer shows a LO port to RF port isolation above 20 dB in all W-band. Its conversion gain is up to 3 dB with a 3 dB RF bandwidth more than 10 GHz. With a 10 dBm LO signal, the RF input 1 dB compression point is higher than −4 dBm around 89 GHz. This mixer consumes 340 mW power with a +4 V supply. All wafers have been thinned to 100 um before measurements.

A five-stage W-band low-noise amplifier (LNA) based on the authors' InP/InGaAs double heterojunction bipolar transistors (DHBTs) process is reported. The LNA achieves a peak gain of 33.1 dB and 7.8 dB noise figure at 81GHz. Its output-related 1 dB compression point (P1dB) lies at 5.8 dBm. The high gain and linearity of the LNA is mainly attributed to the performance of the DHBTs exhibiting a high breakdown voltage (BVceo>8.7V), a current gain cutoff frequency (fT) of 167GHz, and a maximum oscillation frequency (fmax) of 265GHz.

We present a support vector regression-based adaptive divided difference filter (SVRADDF) algorithm for improving the low state estimation accuracy of nonlinear systems, which are typically affected by large initial estimation errors and imprecise prior knowledge of process and measurement noises. The derivative-free SVRADDF algorithm is significantly simpler to compute than other methods and is implemented using only functional evaluations. The SVRADDF algorithm involves the use of the theoretical and actual covariance of the innovation sequence. Support vector regression (SVR) is employed to generate the adaptive factor to tune the noise covariance at each sampling instant when the measurement update step executes, which improves the algorithm’s robustness. The performance of the proposed algorithm is evaluated by estimating states for (i) an underwater nonmaneuvering target bearing-only tracking system and (ii) maneuvering target bearing-only tracking in an air-traffic control system. The simulation results show that the proposed SVRADDF algorithm exhibits better performance when compared with a traditional DDF algorithm.

A method for loop circuit stability analysis is introduced through investigating its closed-loop admittance and open-loop impedance. This method has wider adaptability and less limitation than the traditional approach which uses open-loop power-wave transfer function. A 6-GHz HBT oscillator is designed to verify this method. The measurement result shows the effeteness of the proposed method while the traditional method fails.

This paper presents an initial design of a single-ended gate mixer in self-developed InP High Electron Mobility Transistor (HEMT) technology and its critical parameters measured from 75 GHz to 110 GHz. This mixer realizes a fair conversion loss between 8 dB to 14 dB in full W-Band both in up and down conversion mode, and a 1-dB input compression points more than 0 dBm with the LO pumped at 89 GHz or 94 GHz. All measurement results above are illustrated and analyzed briefly. In a conclusion, it demonstrates the potentials and possibilities to develop passive mixers in W-Band with this process in more complicated structures.

Environmentally recycled liginsulfonate were successfully employed for the facile synthesis of mesoporous NiO materials. The XRD, SEM, TEM and N2 adsorption-desorption analysis were performed for characterizing the structure and surface properties of resultant NiO. The proximate globular structure of lignin macromolecules played an templating role in the formation of mesoporous framework of NiO. The fabricated NiO nanostructures had high specific surface area (193.8 m2/g), large pore volume (0.42 cm3/g), and narrow pore size distribution making them ideal candidates for supercapacitor applications. CV, ESI and galvanostatic constant-current charge/discharge tests showed that the fabricated mesoporous NiO had high specific capacitance (342 F⋅g−1) and good circulatory stability. Furthermore, the mesoporous NiO showed a good rate capability, which is due to that the ordered mesopores did not limit the ion motion within the pores. The results suggest that resultant NiO mesostructures are a promising supercapacitor electrode material.

A two-stage double heterojunction bipolar transistor (DHBT) power MMIC fabricated in InP technology is realized using coplanar waveguide structure. The output cell unit consists of four parallel cascode fingers. Sixteen fingers are at output stage from which the power is combined. Broad-band, low-loss matching networks lead to high gain and high combining efficiency. The chip area is 1.5×1.7 mm2. Measurements show that small signal gain is above 20 dB over 75.5 GHz ∼ 84.5 GHz frequency band. Simulated saturated power is 19.7 dBm @ 89 GHz and the actual output power is to be measured once the W-band power source arrive.

This paper presents a 79 GHz sub-harmonic mixer (SHM) design based on a self-developed 1 um InP DHBT process. In this design, a low frequency local oscillator (LO) input signal at 39.5 GHz is doubled to W-band and a radio frequency (RF) signal ranging from 80 GHz to 86 GHz is down-converted to the intermediate frequency (IF) band with a best conversion gain around 1 dB at 83 GHz. As the knowledge of authors, it is the first attempt to implement an InP DHBT based SHM with a LO doubler in W-band. Due to lacking of available RF sources, the testing is realized with one port of an output power fixed Vector Network Analyzer enhanced by a frequency up-conversion module.

Two MMIC amplifiers have been developed in coplanar technology using 50-nm InAlAs/InGaAs HEMTs. The first is a sing-stage amplifier which used balanced double-stub matching networks for both input and output impedances matching. Measured gain is 8.2 dB @ 81.3 GHz, and the 3-dB bandwidth is at least 13.7 GHz. The second is a two-stage common-source power amplifier. A “#” type distributed transmission line networks has been developed and applied to inter-stage and output stage matching networks. This technique propose a new and efficient approach for impedance matching between transistors where DC blocking and separate bias supplies to the active devices are required. Measured gain is 10.1 dB @ 84 GHz and the 3-dB bandwidth is 14.7 GHz. The saturated power is 11.6 dBm @ 85 GHz, 3.6 dB higher than the above-mentioned single-HEMT amplifier. Measured data are in agreement with the simulation results.

A full W-band low noise amplifier (LNA) module is designed and fabricated. A broadband transition is introduced in this module. The proposed transition is designed,optimized based on the results from numerical simulations. The results show that 1 dB bandwidth of the transition ranges from 61 to 117 GHz. For the purpose of verification,two transitions in back-to-back connection are measured. The results show that transmission loss is only about 0.9-1.7 dB. This transition is used to interface integrated circuits to waveguide components. The characteristic of the LNA module is measured after assembly. It exhibits a broad bandwidth of 75 to 110 GHz,and has a small signal gain above 21 dB. The noise figure is lower than 5.2 dB throughout the entire W-band (below 3 dB from 89 to 95 GHz) at room temperature. The proposed LNA module exhibits potential for millimeter wave applications due to its high small signal gain,low noise,and low DC power consumption.

On-wafer S-parameter de-embedding techniques from 0.1 to 110 GHz are researched. The solving results of thru-reflect-line (TRL) and line-reflect-match (LRM) de-embedding algorithms, when the input and output ports are asymmetric, are given. The de-embedding standards of TRL and LRM are designed on an InP substrate. The validity of the de-embedding results is demonstrated through two passive components, and the accuracy of TRL and LRM de-embedding techniques is compared from 0.1 to 110 GHz. By utilizing an LRM technique in 0.1–40 GHz and a TRL technique in 75–110 GHz, the intrinsic S-parameters of active device HBT in two frequency bands are obtained, and comparisons of the extracted small-signal current gain and the unilateral power gain before and after de-embedding are presented. The whole S-parameters of actual DUT from 0.1 to 110 GHz can be obtained by interpolation.

A W-band frequency doubler MMIC is designed and fabricated using 1-μm InP DHBT technology. Active balun is employed to transform the single-ended signal into differential output. Push—push configuration loaded with harmonic resonant network is utilized to acquire the second harmonic frequency. A multi-stage differential structure improves the conversion gain and suppresses the fundamental frequency. The MMIC occupies an area of 0.55 × 0.5 mm2 with 18 DHBTs integrated. Measurements show that the output power is above 5.8 dBm with the suppression of fundamental frequency below −16 dBc and the conversion gain above 4.7 dB over 75–80 GHz.

A two-stage MMIC power amplifier has been realized by use of a 1-μm InP double heterojunction bipolar transistor (DHBT). The cascode structure, low-loss matching networks, and low-parasite cell units enhance the power gain. The optimum load impedance is determined from load-pull simulation. A coplanar waveguide transmission line is adopted for its ease of fabrication. The chip size is 1.5 × 1.7 mm2 with the emitter area of 16 × 1 μm × 15 μm in the output stage. Measurements show that small signal gain is more than 20 dB over 75.5–84.5 GHz and the saturated power is 16.9 dBm @ 79 GHz with gain of 15.2 dB. The high power gain makes it very suitable for medium power amplification.

We demonstrate the self-assembly of highly dispersed NiO nanoparticles embedded in lignin-derived mesoporous carbon (MPC) frameworks. Self-assembly is induced by evaporation of the solvent from a mixture of metal-containing liquid crystalline mesophases of lignin-derived polymers and transition metal nitrate hydrate, which yielded NiO@MPC nanostructures at 600 °C under a N2 atmosphere. The microstructure and morphology of the NiO@MPC are characterized by XRD, TEM and BET. The results show that the NiO nanoparticles are highly dispersed in a mesoporous carbon matrix. The NiO@MPC composites show metal oxide contents in the range 49–79 wt%, high surface areas (503–802 m2 g−1), uniform pore sizes (≈3.7 nm), various porous distributions and large pore volumes (0.46–0.68 cm3 g−1). Electrochemical studies were carried out by measurement of cyclic voltammetry (CV) and charge–discharge tests. The results demonstrate that the NiO@MPC composites have high specific capacitance (880.2 F g−1 at a current density of 1.0 A g−1) and display good retention. 90.9% of the specific capacitance is retained when the current density changes from 1 A g−1 to 10 A g−1 in the charge–discharge tests and 93.7% of the specific capacitance is retained after 1000 charge–discharge cycles. Thus, the NiO@MPC composites are promising supercapacitor electrode materials.