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The effective spin Hamiltonian method is widely adopted to simulate and understand the behavior of magnetism. However, the magnetic interactions of some systems, such as itinerant magnets, are too complex to be described by any explicit function, which prevents an accurate description of magnetism in such systems. Here, we put forward a machine learning (ML) approach, applying an artificial neural network (ANN) and a local spin descriptor to develop effective spin potentials for any form of interaction. The constructed Hamiltonians include an explicit Heisenberg part and an implicit non-linear ANN part. Such a method successfully reproduces artificially constructed models and also sufficiently describe the itinerant magnetism of bulk Fe3GeTe2. Our work paves a new way for investigating complex magnetic phenomena (e.g., skyrmions) of magnetic materials., 14 pages, 3 figures

The discovery of H3S and LaH10 is an important step towards the development of room temperature superconductors which fuels the enthusiasm for finding promising superconductors among hydrides at high pressure. In the present study, three new and stable stoichiometric MoH5, MoH6 and MoH11 compounds were found in the pressure range of 100–300 GPa. The highly hydrogen-rich phase of Cmmm-MoH11 has a layered structure that contains various forms of hydrogen: H, H2− and H3− units. It is a high-Tc material with an estimated Tc value in the range of 165–182 K at 250 GPa. The same structures are also found in NbH11, TaH11, and WH11, each material showing Tc ranging from 117 to 168 K. By combining the method of using two coupling constants λopt and λac, and two characteristic frequencies (optical and acoustic) with first-principle calculations, we found that the high values of Tc are mainly caused by the presence of high frequency optical modes, but the acoustic modes also play a noticeable role.

In this work, we report on the monolithic integrated photodetectors (PDs) in InGaN/GaN light-emitting diodes (LEDs) to monitor the fluctuation of LED intensity over time. The effect of PD position on the light-receiving performance is studied through ray-trace simulation. Three LED-PD devices with different PD positions are fabricated via standard microfabrication processes, and a series of experimental measurements are performed to examine their performances. The design of the PD located in the center of the LED exhibits a 58% increase in the detected photocurrent and has less influence on the emission profile of the LED, compared with the PD formed at the edge. The white light emission is demonstrated by encapsulating the LED-PD device with yellow phosphor and the on-chip PD shows highly similar sensing behaviors as the external Si-based photodiode. Compared with the traditional off-chip detection scheme, the optimal monolithic PD design can provide comparable sensing capabilities, higher compactness, insensitivity to ambient lighting, and less influence on the LED emission profile, making it highly suitable for real-time monitoring of LED intensity variations in various practical and scientific lighting applications.

A novel ohmic contact formation mechanism is revealed for the annealed Ta0.83 Al0.17/Au stacks on non-recessed i-AlGaN/GaN. It is demonstrated that the contact metal alloy mainly composed by Au penetrates the AlGaN layer without apparent Ta-related solid phase reactions, establishing a spike-free contact to the 2D electron gas. A low contact resistivity of $0.14\Omega ~\cdot $ mm (4.24E- $7~\Omega \cdot $ cm2) is then obtained after 900 °C/60s annealing.

This article reports on a design journey for Sc x Al1 – N -based dual-mode hybrid quasi-surface and bulk acoustic wave (quasi-SAW/BAW) resonators. Four types of acoustic excitation configurations are proposed in these designs based on Sc x Al1– x N/6H-SiC stack architectures. The influence of Sc x Al1– x N materials, film thickness, and device configurations on the performance is investigated. After design optimization, the final dual-mode hybrid quasi-SAW/BAW resonators comprise of top electrode, partially etched Sc x Al1– x N pillars, and bottom electrode, which are stacked on a 6H-SiC substrate. The coupled quasi-SAW and BAW excited in the hybrid resonators enhance the resonance for both quasi-Rayleigh and quasi-Sezawa modes which results in a high effective coupling coefficient ( K eff2) and phase velocity ( ${v}$ ). Simulation results show that the optimized hybrid quasi-SAW/BAW resonator based on Mo/Sc0.4 Al0.6N/Mo/6H-SiC configuration with SiO2 filling the grooves has a remarkable K eff2 value of 14.55% and a high ${v}$ above 7500 m/s, which make this kind of dual-mode hybrid quasi-SAW/BAW resonators have great potential in wideband and high-frequency applications.

Summary Background No standard treatment exists for advanced chordoma. Apatinib has been found to have promising efficacy and manageable adverse effects for the treatment of solid tumours. We aimed to investigate the safety and antitumour activity of apatinib in patients with advanced chordoma. Methods We did a single-arm, phase 2 study at one tertiary hospital in Shanghai, China. Eligible patients were aged 18–75 years, with histologically confirmed advanced chordoma that was unresectable or resectable only through demolitive surgery, who had previously received surgical treatment, with at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, evidence of tumour progression on enhanced CT or MRI in the previous 6 months, and an Eastern Cooperative Oncology Group performance status of 0–2. Patients received oral 500 mg apatinib once daily until disease progression or unacceptable toxicity. The co-primary endpoints were progression-free survival and objective response rate according to RECIST 1.1 and Choi criteria by investigator assessment. Progression-free survival was assessed in the intention-to-treat population. Objective response rate was assessed in the per-protocol population, which included all enrolled patients who were compliant with the protocol and had at least one post-baseline assessment. Safety was analysed in all patients with complete safety data. This study is ongoing, but recruitment is complete. This study is registered with Chictr.org.cn , ChiCTR-OIC-17013586. Findings Between Aug 21, 2017, and May 31, 2019, we screened 32 patients, of whom 30 were enrolled. Median follow-up was 14·2 months (IQR 9·4–19·7). Of the 27 patients included in the per-protocol population, one patient (3·7%; 95% CI 0–11·3) achieved an objective response according to RECIST, and seven patients (25·9%; 8·3–43·6) achieved an objective response according to Choi criteria. Median progression-free survival was 18 months (95% CI 3–34) according to RECIST and 18 months (3–33) according to Choi criteria. The most common treatment-related grade 3 adverse events were hypertension (seven [24%] of 29 patients) and proteinuria (two [7%]). No treatment-related grade 4 adverse events or treatment-related deaths were observed. Interpretation To our knowledge, this is the first trial of apatinib for the treatment of advanced chordoma. Apatinib shows promising activity and manageable toxicity and thus might be an option for the treatment of advanced chordoma. Funding None.

On 17 August 2015, an Mw 4.6 earthquake occurred northwest of Fort St. John, British Columbia, possibly induced by hydraulic fracturing (HF). We use data from eight broadband seismometers located ∼50 km from the hypocenter to detect and estimate source parameters of more than 300 events proximal to the mainshock. Stress-drop values estimated using seismic moment and corner frequency from single-event spectra and spectral ratios range from ∼1 to 35 MPa, within the typical range of tectonic earthquakes. We observe an ∼5-day delay between the onset of fluid injection and the mainshock, a b-value of 0.78 for the sequence, and a maximum earthquake magnitude larger than the prediction based on the total injection volume, suggesting that the Mw 4.6 sequence occurred on a pre-existing fault and that the maximum magnitude is likely controlled by tectonic conditions. Results presented here show that pre-existing fault structures should be taken into consideration to better estimate seismic hazard associated with HF operations and to develop schemes for risk mitigation in close proximity to HF wells.

As an optical material, Y2O3 transparent ceramics are desirable for application as laser host materials. However, it is difficult to sinter and dense of Y2O3 hinders the preparation of high-quality optical ceramics via traditional processes. In this work, we use La2O3 as a sintering aid for fabricating high-transparency Y2O3 ceramics using a vacuum sintering process. It is demonstrated that the in-line optical transmittance of 15.0 at% La-doped Y2O3 at a wavelength of 1100 nm achieves a transmittance of 81.2%. A sintering kinetics analysis reveals that a grain-boundary-diffusion-controlled mechanism dominates the faster densification at high La3+ concentrations. It is also shown that both the mechanical and thermal properties of Y2O3 transparent ceramics are significantly improved upon the increase of La2O3 sintering additives. The results indicate that a La-doped Y2O3 transparent ceramic is a promising candidate for a laser host material.

Up-conversion (UC) luminescence properties of Nd:Y2O3transparent ceramics are investigated. It is shown that, under a laser excitation of 808 nm, the samples exhibit significant UC emission. With an increase in the Nd3+ concentration, the intensity of green emission decreases, while the intensity of red emission first increases and then decreases. In particular, both green and red UC emissions are found to be two-photon processes, but with different quantum transition mechanisms. In addition, the dependence of UC emission intensity on the pumping power is studied. Our studies indicate that Nd:Y2O3 transparent ceramics are promising candidates as short-wavelength UC laser material.

Our paper is concerned with the specific hydrogen compound MoH

Background Early lung cancer detection remains a clinical challenge for standard diagnostic biopsies due to insufficient tumor morphological evidence. As epigenetic alterations precede morphological changes, expression alterations of certain imprinted genes could serve as actionable diagnostic biomarkers for malignant lung lesions. Results Using the previously established quantitative chromogenic imprinted gene in situ hybridization (QCIGISH) method, elevated aberrant allelic expression of imprinted genes GNAS, GRB10, SNRPN and HM13 was observed in lung cancers over benign lesions and normal controls, which were pathologically confirmed among histologically stained normal, paracancerous and malignant tissue sections. Based on the differential imprinting signatures, a diagnostic grading model was built on 246 formalin-fixed and paraffin-embedded (FFPE) surgically resected lung tissue specimens, tested against 30 lung cytology and small biopsy specimens, and blindly validated in an independent cohort of 155 patients. The QCIGISH diagnostic model demonstrated 99.1% sensitivity (95% CI 97.5–100.0%) and 92.1% specificity (95% CI 83.5–100.0%) in the blinded validation set. Of particular importance, QCIGISH achieved 97.1% sensitivity (95% CI 91.6–100.0%) for carcinoma in situ to stage IB cancers with 100% sensitivity and 91.7% specificity (95% CI 76.0–100.0%) noted for pulmonary nodules with diameters ≤ 2 cm. Conclusions Our findings demonstrated the diagnostic value of epigenetic imprinting alterations as highly accurate translational biomarkers for a more definitive diagnosis of suspicious lung lesions.

In this work, we use Si/Tl5Al1/TiN for a source/drain ohmic contact to demonstrate an ultra-low contact resistance of 0.11 Ω mm (ρc = 2.62 × 10−7 Ω cm2) on non-recessed i-InAlN/GaN heterostructures. The Ti5Al1 alloy was used to suppress the out-diffusion of Al and extract N from the InAlN layer, which aided the formation of ohmic contact by improving the tunneling efficiency of electrons, as we have reported in the past work. A thin Si inter-layer combined with the Ti5Al1 alloy is proposed to further reduce contact resistance. A heavy n-type InAlN layer was obtained through doping with Si atoms to improve the tunneling transport of electrons. Furthermore, the TiN inclusions penetrated into the GaN channel because the in-diffused Si promoted the decomposition of GaN at a high annealing temperature and the in-diffused Ti reacted with GaN. These TiN inclusions provided direct contact with two-dimensional electron gas, offering an additional path for the injection of electrons into the channel. The tunneling and spike mechanism worked alternately to lower the contact resistance at different annealing temperatures (dividing at 900 °C), implying that the joint effect of tunneling and the spike mechanism was initially promoted in the formation of ohmic contact. The mechanism of this Si/Ti5Al1/TiN ohmic contact was fully understood through microscopic and thermodynamic analyses. These results shed light on the mechanism for the formation of ohmic contact in a gold-free metal stack for GaN-based HEMTs.

Wearable strain sensors have been widely used for human activity monitoring. Most reported strain sensors have mainly focused on material engineering, high stretchability and large gauge factors. Few works have focused on strain sensor’s robustness and reliability, including low hysteresis, good long-term stability, good electrode material stability, and low coupling effects under multi-input signals, which are the factors that limit practical strain sensor applications. To develop a high-performance strain sensor, we propose a flexible capacitive sensor structure with three-dimensional (3D) interdigital electrodes fabricated by vertically aligned carbon nanotubes. Compared with a traditional resistive strain sensor and a capacitive strain sensor with vertical sandwich electrodes, a strain sensor with horizontal parallel interdigital electrodes can benefit from low cross talk in terms of the normal force and improve substrate transparency. Additionally, embedding 3D electrodes into the substrate improves ultrahigh robustness with a low-pressure coupling effect under normal force. Moreover, compared with other reported works, the electrode variation under strain is small (less than 1.6%), which means that the perturbation of inert properties on device performance is small. Finally, the fabricated strain sensor achieves an ultralow hysteresis (0.35%), excellent pressure-insensitive performance (less than 0.8%), fast response (60 ms), good long-term stability, and good transparency. As an application example, a flexible strain sensor was successfully demonstrated as a wearable device for the precise monitoring of different types of human activities, including bending of the finger, knee, elbow, wrist, and neck with large strain signals and small strain signals generated by a mouth-opening activity. This excellent performance indicates that the flexible strain sensor is a promising candidate for human motion detection, soft robotics, and medical care.

Artificial tactile sensing for robots is a counterpart to the human sense of touch, serving as a feedback interface for sensing and interacting with the environment. A vision-based tactile sensor has emerged as a novel and advantageous branch of artificial tactile sensors. Compared with conventional tactile sensors, vision-based tactile sensors possess stronger potential thanks to acquiring multimodal contact information in much higher spatial resolution, although they typically suffer from bulky size and fabrication challenges. In this article, we report a thin vision-based tactile sensor that draws inspiration from natural compound eye structures and demonstrate its capability of sensing three-dimensional (3D) force. The sensor is composed of an array of vision units, an elastic touching interface, and a supporting structure with illumination. Experiments validated the sensor's advantages, including competitive spatial resolution of deformation as high as 1016 dpi on a 5 × 8 mm

Hydrogen-rich compounds are being extensively explored theoretically and experimentally as potential hydrogen storage materials. In this work, we predicted a hydrogen-rich compound rhodium trihydride ($\mathrm{Rh}{\mathrm{H}}_{3}$) with a high volumetric hydrogen density of 212.5 g/L by means of ab initio calculations. The $\mathrm{Rh}{\mathrm{H}}_{3}$ with Pnma symmetry is thermodynamically stable and accessible through synthesis above 40 GPa. The compound is dynamically and mechanically stable at ambient pressure. Further calculation suggests a probable dehydrogenation temperature ${T}_{\mathrm{des}}$ of $65{\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$ at ambient pressure with decomposition route to $\mathrm{Rh}+{\mathrm{H}}_{2}$. High volumetric hydrogen density and moderate dehydrogenation temperature place $\mathrm{Rh}{\mathrm{H}}_{3}$ as one of the best hydrogen storage materials. Our work encourages the experimental synthesis of $\mathrm{Rh}{\mathrm{H}}_{3}$ at high pressure.

Harvesting the potential performance of GaN-based devices in terms of the areal power density and reliability, relies on the efficiency of their thermal management. Integration of extremely high thermal conductivity Single-crystalline CVD-diamond serves as an efficient solution to their strict thermal requirements. However, the major challenge lies in the Thermal Boundary Resistance (TBR) at the interface of GaN/Diamond or SiC/Diamond. Junction temperature of the device shows a sensitivity of 1.28°C for every unit of TBR for GaN-on-Diamond compared to 0.43°C for every 10 units of TBR for GaN/SiC-on-Diamond. Finite Volume Thermal Analysis has shown a limit of around 22 m2K/GW beyond which the merit of proximity to the heat-source for GaN-on-Diamond can no more outperform GaN/SiC-on-Diamond. Besides, due to the temperature dependency of the thermal conductivity K, an increase in the temperature causes an increase in the thermal resistivity of the device which is more significant in high power operations. Simplified assumption of constant K overestimates the device performance by resulting in 17.4°C lower junction temperature for the areal power density of 10W/mm. Other part of the project regarding the in-house growth of CVD-diamond to be bonded to the GaN device has been simultaneously in progress.

A robust process for Au-free ohmic contact formation is demonstrated by a direct contact of TixAly alloy film on non-recessed i-AlGaN/GaN. Using this novel TixAly alloy instead of multilayers as contact metals, an ultra-low contact resistivity of $ mm is achieved for Ti5Al1 alloy on i-AlGaN/GaN after 880 °C/60s annealing.

Recess processes for the fabrication of normally-off GaN HEMTs generally compromise devices’ on-state performance. In this work, recess-free quasi-normally-off GaN HEMTs with a threshold voltage of 0.24 V is realized by local control of two-dimensional electron gas (2DEG) density. The devices feature a $0.1~{\mu }\text{m}$ gate length, SiNx stress liner, and comb gate. SiNx liner can provide significant stress to AlGaN/GaN heterostructure in the scaled gate region. The additional stress translates to the additional electric field and depletes the 2DEG in the gate region. As a result, the quasi-normally-off operation is achieved. Furthermore, the comb gate structure is introduced to suppress the short channel effects, supported by TCAD simulation. The quasi-normally-off devices’ excellent on-state performances are benchmarked against the normally-off devices reported recently and a p-GaN HEMT purchased from a commercial foundry. The results support strain engineering as a promising technique to pursue the normally-off operation of GaN HEMTs.

This paper demonstrates a new fabrication process for gallium nitride high-electron mobility transistors (HEMTs) free of plasma damages in the sub-100 nm T-shape gate area. The common peeling-off problems of electron beam resists during gate metal deposition process were solved by introducing a fluorine plasma treatment process before gate metal deposition. By combining dry and wet etching processes appropriately, an on/off ratio of 107 at a drain-to-source voltage of 1 V was achieved. This work also investigated the short channel effect in devices with gate lengths from 70 to 440 nm. Reducing gate length results in decrease of threshold voltage due to the drain-induced barrier-lowering effect. Current gain cut-off frequency fT and maximum oscillation frequency fmax increase while gate length reduces till 250 nm. However, below 250 nm, fT and fmax no longer increase while gate length reduces till sub-100 nm, which reflect the short channel effect.

Hybrid heterojunctions based on two-dimensional (2D) and conventional three-dimensional (3D) materials provide a promising way toward nanoelectronic devices with engineered features. In this work, we investigated the band alignment of a mixed-dimensional heterojunction composed of transferred MoS2 on β-Ga2O3($$ 2- $$2-01) with and without nitridation. The conduction and valence band offsets for unnitrided 2D-MoS2/3D-β-Ga2O3 heterojunction were determined to be respectively 0.43 ± 0.1 and 2.87 ± 0.1 eV. For the nitrided heterojunction, the conduction and valence band offsets were deduced to 0.68 ± 0.1 and 2.62 ± 0.1 eV, respectively. The modified band alignment could result from the dipole formed by charge transfer across the heterojunction interface. The effect of nitridation on the band alignments between group III oxides and transition metal dichalcogenides will supply feasible technical routes for designing their heterojunction-based electronic and optoelectronic devices.

BackgroundThe extracellular matrix has been critically associated with the tumorigenesis and progression of Ewing sarcoma (ES). However, the regulatory and prognostic roles of tenascin-C (TNC) in ES remain unclear.MethodsTNC expression was examined in specimens by immunohistochemistry, and the association of TNC expression with ES patient survival was also analysed. TNC-knockout cell lines were constructed using CRISPR/Cas9 methods. In vitro experiments and in vivo bioluminescent imaging using BALB/c nude mice were conducted to evaluate the effect of TNC on ES tumour progression. RNA sequencing was performed, and the underlying mechanism of TNC was further explored.ResultsTNC was overexpressed in ES tissue and cell lines, and TNC overexpression was associated with poor survival in ES patients. TNC enhanced cell proliferation, migration and angiogenesis in vitro and promoted ES metastasis in vivo. The oncoprotein EWS-FLI1 profoundly increased TNC expression by directly binding to the TNC promoter region. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) upregulation induced by Yes-associated protein (YAP) activation was responsible for TNC-regulated ES tumour progression. Activated integrin α5β1 signalling might be correlated with YAP dephosphorylation and nuclear translocation.ConclusionsTNC may promote ES tumour progression by targeting MALAT1 through integrin α5β1-mediated YAP activation.

In this work, a thin-film transistor gas sensor based on the p-N heterojunction is fabricated by stacking chemical vapor deposition-grown tungsten disulfide (WS2) with a sputtered indium–gallium–zi...

Thermoelectric materials can effectively convert waste heat into electrical energy and receive more and more attention. Zintl phase Mg3Sb2 is a typical layered thermoelectric material and the anisotropy in crystalline structure induces strong anisotropy in its thermoelectric properties. As a result, polycrystalline Mg3Sb2 usually can not achieve the maximum thermoelectric performance. Our research proves that the dimensionality reduction in material structure can not only avoid certain crystalline direction's poor thermoelectric properties but also effectively reduce the lattice thermal conductivity. Within the framework of the density functional theory, the thermoelectric performance of two-dimensional Mg3Sb2 mono layer is accurately investigated. The ZT value of the Mg3Sb2 nano-thin film can reach 2.5 at 900 K, which is larger than that of the bulk. The theoretical results indicate that the process of nano-engineered structure can significantly enhance the energy conversion efficiency of thermoelectrics.

The search for high-temperature superconductivity is one of the research frontiers in physics. In the sulfur hydride system, an extremely high Tc (∼200 K) has been recently developed at pressure. However, the Meissner effect measurement above megabar pressures is still a great challenge. Here, we report the superconductivity identification of sulfur hydride at pressure, employing an in situ alternating-current magnetic susceptibility technique. We determine the superconducting phase diagram, finding that superconductivity suddenly appears at 117 GPa and Tc reaches 183 K at 149 GPa before decreasing monotonically with increasing pressure. By means of theoretical calculations, we elucidate the variation of Tc in the low-pressure region in terms of the changing stoichiometry of sulfur hydride and the further decrease in Tc owing to a drop in the electron–phonon interaction parameter λ. This work provides a new insight into clarifying superconducting phenomena and anchoring the superconducting phase diagram in the hydrides.

As high-performance dielectric material, small sizes of barium titanate (BaTiO3) are desirable for the application of multilayer ceramic capacitors. Herein, we synthesized ultrafine BaTiO3 powders with mean particle size of (dav.) 156 nm, tetragonality (c/a) of 1.0092 and specific surface area (SBET) of 6.09 m2/g by two-step sintering process. Kinetic analysis of solid-state reaction reveals that the phase-boundary-controlled mechanism dominated the reaction process in two-step sintering process compared with one-step sintering process dominated by the first-order mechanism. It is also shown that enhanced nucleation in two-step calcination is beneficial for improving the tetragonality. In particular, the dielectric constant and dielectric loss of BaTiO3 ceramics at the Curie temperature are found to be about 12800 and 0.003. This work demonstrates a strategy to trigger a method which can effectively improve the dielectric properties of BaTiO3 ceramic.

Transparent ceramic is considered to be a fascinating material with high photonic quality for a diverse range of applications. Here, we fabricated series of highly transparent Yb:Y2O3 (Yb:1.0, 3.0, 5.0, 7.0 and 9.0 at.%) ceramics via a vacuum solid-state reactive sintering. The room temperature up-conversion spectra for blue emissions are observed under the laser excitation of 980 nm. It is shown that the content of Yb3+ plays an important role in emission efficiency. Especially, the sample containing 7.0 at.% Yb3+ achieves the strongest cooperative luminescence. Analysis reveals that Yb3+-Yb3+ cluster cooperating in Y2O3 transparent ceramics takes place via phonon-assist energy transfer mechanism. Furthermore, the blue emission spectroscopy and decay lifetime of 7.0 at.% Yb:Y2O3 are also discussed.

The increasing decomposition temperature of solid ammonia borane under high pressure introduces a solid–solid phase transition preceding decomposition. An earlier X-ray diffraction experiment sugge...

Structure prediction studies on Ca-H binary systems under high pressures were carried out, and the structures of calcium hydrides in earlier works were reproduced. The previously unreported composition of CaH

The high-pressure phase diagrams of binary Se–N system have been constructed using the CALYPSO method and first-principles calculations. Four stable compounds (Cmc21-SeN2, P21/m-SeN3, P1-SeN4, and...

Superionic states simultaneously exhibit properties of a fluid and a solid. Proton (H

The humidity sensor is an essential sensing node in medical diagnosis and industrial processing control. To date, most of the reported relative humidity sensors have a long response time of several seconds or even hundreds of seconds, which would limit their real application for certain critical areas with fast-varying signals. In this paper, we propose a flexible and low-cost humidity sensor using vertically aligned carbon nanotubes (VACNTs) as electrodes, a PDMS-Parylene C double layer as the flexible substrate, and graphene oxide as the sensing material. The humidity sensor has an ultrafast response of ~20 ms, which is more than two orders faster than most of the previously reported flexible humidity sensors. Moreover, the sensor has a high sensitivity (16.7 pF/% RH), low hysteresis (