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This paper presents an integrated operational amplifier (OPAMP) consisting of only n-type metal oxide thin-film transistors. In addition to using positive feedback in the input differential pair, a transconductance-enhancement topology is applied to improve the gain of the OPAMP. The OPAMP has a voltage gain ( $A_{v}$ ) of 29.54 dB over a 3-dB bandwidth of 9.33 kHz at a supply voltage of 15 V. The unity-gain frequency, phase margin (PM), and dc power consumption ( $P_{\mathrm{ DC}}$ ) are 180.2 kHz, 21.5° PM and 5.07 mW, respectively.

Background To explore the clinical characteristics of neurocutaneous melanosis (NCM) in adult patients to help improve diagnosis and treatment of this disease, we present a rare case of an adult patient suffering from NCM with malignant melanoma, as well as a review of the relevant Chinese and English literature. Case Description The patient reported here plus the patients identified in our literature review total 30 adults with NCM (20 males [66.7%] and 10 females [33.3%]), age 19–65 years (average, 27.9 years). These include 24 cases of malignant melanoma (80.0%), 3 cases of melanocytoma (10.0%), 2 cases of diffuse melanocytosis (6.7%), and 1 case of unknown pathology (3.3%). Satellite nevi were reported in 25 cases (83.3%) and in 5 cases their presence was unknown (16.7%). Intracranial lesions were present in 28 cases (93.3%), and intraspinal lesions were present in 2 cases (6.7%). There are 4 cases of combined hydrocephalus (13.3%), and 2 cases of combined Dandy–Walker deformity (6.7%). Conclusions NCM is a rare disease, especially in adults. With the onset of symptoms, the diagnosis is generally confirmed. In children with congenital giant nevus, regular periodic surveys of the central nervous system (brain and spinal cord) with magnetic resonance imaging or cerebrospinal fluid analysis should be performed to diagnose NCM. Active treatment should be undertaken to improve the prognosis.

Large quantities of waste clay bricks from construction and demolition (C&D) waste are currently stockpiled in landfills, which is an environmentally, technically, and economically detrimental procedure. In this work, waste clay bricks powder (WCBP) was assessed to determine its feasibility as an alternative to cement for ultra-high-strength and ultra-high ductility cementitious composites (UHS-UHDCCs). The influences of WCBP on the fluidity, hydration, mechanical properties, fiber/matrix interface performances, autogenous shrinkage, and ecological overload capacity of UHS-UHDCC with different replacement levels ranging from 0 to 50% were investigated. The results indicate that WCBPs reduce the fluidity of the UHS-UHDCC matrix. WCBP content of 20% slightly accelerates the hydration process and exhibits the highest compressive and flexural strength in the specimens. Moreover, all UHS-UHDCCs achieve strain-hardening characteristics and exhibit a tensile strain capacity of 3.18–5.47%. UHS-UHDCC with 20% WCBP obtains excellent ultimate tensile stress and tensile strain capability, reaching around 9.34 MPa and 3.18%, respectively. The performance of the interface frictional bond ( τ ) with different WCBP content was obtained through single-fiber pullout tests, which reasonably explained the macroscopic tensile properties of UHS-UHDCC. The average interface frictional bond ( τ ) between the fiber and matrix of UHS-UHDCC reaches the maximum 1.72 MPa in the WCBP20 specimen. The average slip hardening coefficient ( β ) of UHS-UHDCC is distributed between 0.0031 and 0.0075 and tends to be excellent in the WCBP20 specimen. The theoretical fiber bridging stress vs crack displacement relationship of UHS-UHDCC was calculated through the limitation of interface parameters, which had an excellent correlation with the experimental results. Furthermore, the introduction of WCBP remarkably reduces the autogenous shrinkage of UHS-UHDCC. The ecological overload capacity of UHS-UHDCC is decreased by the introduction of WCBP, which provides an environmentally friendly solution for the C&D and cement industries.

This paper proposes a pull-up control scheme in the pseudo-CMOS inverter to design a low-power ring oscillator (RO) realized by only n-type transistors. For comparing 11-stages, the proposed RO and the conventional RO are both fabricated by metal–oxide thin-film transistors with the etch stop layer structure. It is measured that the power-delay product of the proposed RO is reduced by more than 50% under the same value of supply voltage. At the same oscillation frequency, the power consumption tends to be reduced by 18% as oscillation frequency increases. Furthermore, the peak-to-peak voltage of the proposed RO can almost receive a full swing at any supply voltage.

To investigate more predictors for acute encephalocele in patients during isolated acute subdural hematoma (ASDH) surgery by using clinical data combined with preoperative cranial computed tomography (CT) scan, so as to provide a basis for the development of a more scientific and reasonable treatment strategy. CT images and medical records of 46 patients who underwent neurosurgery for isolated traumatic acute subdural hematoma were collected. The patients with intra-operative acute encephalocele were grouped as the observation group (n=23), and the patients with no intra-operative acute encephalocele, whose age difference was within 5 years were included in the control group (n=23). The t-test and multivariate logistic regression analyses were carried out to evaluate the influence of clinical variables on acute encephalocele. Meanwhile, whether differences among Thickness of hematoma(TH), Midline shift (MLS), Hounsfield units of white matter (HU-WM), Hounsfield units of hematoma (HU-HT) and basal cistern effaced score (CES) measured by cranial CT could be used as predictors of outcomes in patients with acute encephalocele during subdural hematoma surgery was evaluated. There were no significant differences in age, sex, mechanism of injury, the time from trauma to decompression, and the MLS during surgery between the two groups. However, significant differences in preoperative Glasgow Coma Score (GCS), TH, HU-WM and HU-HT between the two groups were observed. The multivariate logistic regression analysis of radiographic data showed that HU-WM and CES were independent risk factors and strong predictors for intra-operative acute encephalocele. The areas under curve of CES and HU-WM were 0.8459 and 0.8336, respectively. The risk factors for acute encephalocele during ASDH operation are identified in this study. An increased risk of intra-operative acute encephalocele is found in patients with lower preoperative GCS, HU-WM, HU-HT and higher preoperative TH and CES, which should help clinicians to develop a more scientific treatment strategy and improve the survival of such kind of patients.

In 1956, conjectured that, for any positive integer n and any primitive Pythagorean triple (a, b, c) with , the equation has the unique solution (x, y, z) = (2, 2, 2). In this paper, under some conditions, we prove the conjecture for the primitive Pythagorean triples .

Let n > m ⩾ 2 be positive integers and n = (m + 1)l + r, where ⩽ r ⩽ m. Let C be a subset of {0, 1, …, n}. We prove that if $$|C| > \left\{ {\matrix{{\left\lfloor {n/2} \right\rfloor + 1{\rm{ if }}m{\rm{ is old,}}} \cr {ml/2 + \delta {\rm{ if }}m{\rm{ is even,}}} \cr } } \right.$$ , where └x┘ denotes the largest integer less than or equal to x and δ denotes the cardinality of even numbers in the interval [0, min{r,m − 2}], then C − C contains a power of m. We also show that these lower bounds are best possible.

For any electric vehicle on the road, it is inevitable to be influenced by parameter uncertainties and some kinds of disturbance torques, which present challenge for the controller design in the electric vehicle. Therefore, control of the electric vehicle to achieve the safety running requirement becomes important. In this paper, we investigate the control method for electric drive system of the electric vehicle from both theoretical and applied perspectives, then, speed loop inverse based disturbance rejection control strategy is proposed. The proposed approach is illustrated by implementing it into an experimental platform. The experimental results demonstrated that the proposed control method can achieve rapid response to current variation at operating frequency of electric vehicle, and substantially suppress the adverse effect of current variation at high frequency.

The amino groups of aminofluorescein were covalently linked to the carboxyl groups of glycosaminoglycans (GAGs; heparin, heparan sulfate, and the chondroitin sulfates A, B, C, D and E) using 1-ethyl-3-(1,3-dimethylaminopropyl)-carbodiimide and N -hydroxysuccinimide as the catalytic reagents, and fluorescently labeled GAGs were obtained separately. The fluorescently labeled GAGs were transferred onto nitrocellulose-coated glass chips with a manual microarrayer. The retention rate of GAGs on the nitrocellulose membrane after washing was calculated, and their interactions with monoclonal anti-chondroitin sulfate antibody (clone number CS-56) were further studied. The experimental results showed that the retention rates were apparently different between the GAGs and of the order chondroitin sulfate E (51.7%) > chondroitin sulfate A (19.5%) > heparan sulfate (16.4%) > heparin (14.1%) > chondroitin sulfate B (12.3%) > chondroitin sulfate D (10.8%) > chondroitin sulfate C (10.7%). The interaction of GAGs with CS-56 was scientifically compared according to their retention rates on nitrocellulose-carbohydrate chips, and after quantitative calculation, the binding ability of the GAGs to CS-56 is of the order chondroitin sulfate C > D > A > E; furthermore, chondroitin sulfate B, heparin, and heparan sulfate did not show any interaction with CS-56.

Let A be a set of nonnegative integers. For h≥2, denote by hA the set of all the integers representable by a sum of h elements from A. In this paper, we prove that, if k≥3, and A={a0,a1,…,ak−1} is a finite set of integers such that 0=a0

Inverter-fed motors are damaged due to pulse voltage. The situation leads to early failure of insulation. Polyimide is an important insulating material in the inverter-fed motors. Its insulation aging process and failure mechanism are different from traditional AC and DC voltage. In this paper, structure change of polyimide film aging under pulse voltage above partial discharge inception voltage (PDIV) is investigated through scanning electron microscopy (SEM), thermally stimulated current (TSC) and lifetime test. It reveals that the degradation of structure in polyimide propagates from surface to interior with continuous aging, creating three layers in section. In the TSC spectrum, two main well-resolved peaks, namely ? and s, exist in the 20-200°C range. The configuration corresponding to ? peak in polyimide is damaged more severely than the configuration corresponding to s peak and its degradation is accelerated with increase in frequency.

A YBCO racetrack coil was developed for HTS machine applications. The coil was constructed as step-type to fit in the limited space of the machine rotor. Two double-pancake (DP) windings were fabricated for the whole coil that has used 388 m of YBCO wires purchased from American Superconductor Corporation (AMSC). A finite-element method (FEM) software was used to model the coil and the critical currents for each DB winding were estimated. The winding process was introduced in details, including a few accidents occurred during the process. The coil was tested in a liquid nitrogen tank, and the results shows good compliance with the simulation results, which indicates no degradation areas in the windings.

In order to enhance the efficiency of anaerobic digestion of excess sludge, acid-alkali pretreatment method was studied. Three different pretreatment methods (alkali alone,acid-alkali, alkali-acid) were compared to investigate their impacts on hydrolysis and acidification of activated sludge. In addition, their influences on methane-producing in subsequent anaerobic digestion process were also studied. The results showed that the soluble chemical oxygen demand (SCOD) of alkaline treatment alone was about 16% higher than the combining of acid and alkali treatment, SCOD concentration increased to 5406.1 mg x L(-1) after 8 d pretreatment. After treated by acid (pH 4.0, 4 d) and alkali (pH 10.0, 4 d), the acetic acid production and its content in short-chain fatty acids (SCFAs) were higher than other pretreatment methods. And the acetic acid production (as COD/VSS) could reach 74.4 mg x g(-1), accounting for 60.5% of SCFAs. After acid-alkali pretreatment, the C: N ratio of the sludge mixed liquor was about 25, and the C: P ratio was between 35-40, which was more favorable than C: N and C: P ratio of alkali alone and alkali-acid to subsequent anaerobic digestion. The control experiments showed that, after acid-alkali pretreatment, anaerobic digestion cumulative methane yield (CH4/VSS(in)) reached to 136.1 mL x g(-1) at 15 d, which was about 2.5-, 1.6-, and 1.7-fold of the blank (unpretreated), alkali alone pretreatment and alkali-acid pretreatment, respectively. After acid-alkali pretreatment for 8 d and anaerobic digestion for 15 d, the removal efficiency of VSS was about 60.9%, and the sludge reduction effect was better than other pretreatments. It is obvious that the acid-alkali pretreatment method was more favorable to anaerobic digestion and sludge reduction.

A noval all fiber optic Fourier transform spectrometer based on single mode fiber Mach-Zehnder interferometer is reported. The authors designed a piezoelectric optical phase modulator with two centimeter scan scale, which was used to replace the moving mirror of traditonal Fourier transform spectrometer. The 1 310 nm DFB laser was used as reference light source to make equal interval sampling of test light source's interferogram, and to eliminate errors of nonlinear modulation. Through making the inverse Fourier transform to test light source's interferogram, the authors obtained the spectrum of test source. The spectrum of ASE broadband light source was measured by FFTS system, and the experiment result agrees with that tested by grating spectrometer. Finally, the authors utilized fiber grating as sample to measure the resolution of FFTS system, and the spectral resolution is 0.78 cm(-1).

Presently, polyimide film is applied widely in turn-to turn insulation and turn to ground insulation of inverter-fed traction motors as one kind of special project plastic film. In this paper, the measurement of partial discharge is done on nanometer hybrid polyimide film and non nanometer polyimide film with different frequency and different rise time under high-frequency square impulse. Some parameters of PD are discussed based on measurement results. The results showed: gap surface conductivity have greater impact on PD, the main impact of rise time on PD parameters mainly depends on the initial electron delay and the gap dynamic electric field, the interfaces formatted by inorganic nano-filler filling improved the conductivity of the material, the movement of charge along the gap surface become much easier, while nano-materials exist large quantities of shallow traps, so that the PD initial electronic selection engender easily.

It has been shown that the supply waveforms generated by the power converters play a major role in inverter-fed traction motor insulation degradation. The electrical characterization of these insulating materials is often carried out through aging tests which may provide estimation of life under different stress levels and conditions. However, deeper investigation of aging phenomena due to supply voltage waveforms is needed, especially regarding the relation between aging factors and stress conditions. Accelerated aging tests under different supply voltage waveforms and temperature were conducted on twisted pairs simulating inter-turn insulation of inverter-fed traction motor. Tandelta and sample capacity were measured under different testing voltages. Based on analysis of dielectric loss and mechanics of square wave pulses, the experimental results show that PDIV is increasing with the increase of voltage amplitude in the early aging stage. PDIV is affected significantly by space charge accumulation under bipolar waveforms, which is almost independent of frequency among three factors. Little change of temperature has a strong impact on insulation. Impulse amplitude, frequency and temperature have a cooperative effect, which show that strengthening or weakening of each factor will alter trend of other factors effect on insulation.

The title compound, 3(C5H16N2)2+·[V10O28]6−·6H2O, consists of deca­vanadate polyanions, doubly protonated N,N-dimethyl­propane-1,3-diammonium cations (H2dmpn2+) and uncoordinated water mol­ecules. Two crystallographically independent deca­vanadate anions are located across inversion centers. The terminal V=O bond distances are much shorter than the bridging V—O bond distances. The structural components are linked by extensive hydrogen bonding, forming a three-dimension supra­molecular architecture.