Conductivity Distribution Research Articles

Unpredictably Disordered Distribution of Hetero‐Blended Graphene Oxide Flakes with Non‐Identical Resistance in Physical Unclonable Functions

AbstractIn this study, a new concept of physical unclonable functions (PUFs) is introduced comprising reduced graphene oxide (GO) materials. To create a disordered conductivity distribution, two types of GO are used: HGO, are produced by the conventional Hummers’ method, and PGO, produced by Brodie's method with an additional unique purification procedure. It is found that PGO becomes graphene‐like after room‐temperature chemical reduction. These two reduced GOs have a distinct conductivity difference of up to 104 times. By blending these two materials, a random mixture is created that can generate a highly unpredictable electrical signal, serving as an ideal security key with strong randomness and uniqueness. The optimized PUF device, based on this approach, demonstrates excellent performance in generating secure keys.

DeepEIT: Deep Image Prior Enabled Electrical Impedance Tomography.

Neural networks (NNs) have been widely applied in tomographic imaging through data-driven training and image processing. One of the main challenges in using NNs in real medical imaging is the requirement of massive amounts of training data - which are not always available in clinical practice. In this article, we demonstrate that, on the contrary, one can directly execute image reconstruction using NNs without training data. The key idea is to bring in the recently introduced deep image prior (DIP) and merge it with electrical impedance tomography (EIT) reconstruction. DIP provides a novel approach to the regularization of EIT reconstruction problems by compelling the recovered image to be synthesized from a given NN architecture. Then, by relying on the NN's built-in back-propagation and the finite element solver, the conductivity distribution is optimized. Quantitative results based on simulation and experimental data show that the proposed method is an effective unsupervised approach capable of outperforming state-of-the-art alternatives.

Assessing Contaminant Mass Discharge Uncertainty With Application of Hydraulic Conductivities Derived From Geoelectrical Cross‐Borehole Induced Polarization and Other Methods

AbstractA new methodology was developed to support contaminant mass discharge (CMD)‐based risk assessment of groundwater contamination downgradient of point source zones. Geoelectrical cross‐borehole induced polarization (IP) data were collected at a site undergoing in situ remediation of chlorinated solvents for determining 2D hydraulic conductivity (K) distributions with an inversion model resolution of 0.15 m (vertically) x 0.50 m (horizontally) in three control planes from 10 to 20 m depth. Additionally, 18 slug tests and 31 grain size distribution analyses (GSA) from the control planes, were used for K‐estimation. The geometric means and variance of the IP, slug test, and GSA derived K‐estimates were consistent with previously studied sandy aquifers. Furthermore, the vertical variation in K between two geological settings, a sandy till and a meltwater sand formation, was clearly identified by the IP K‐estimates. The vertical variation was backed up by hydraulic profiling tool (HPT) measurements. Random realizations of CMD were simulated based on the cross‐borehole IP derived K‐values. For comparison, the CMD was also estimated with a geostatistical conditional simulation approach, using the data from slug tests and GSAs. The high IP resolution captured the small scale variations in K across the transects and led to CMD predictions with a narrow uncertainty interval, whereas slug test and GSA either under‐ or overestimated the magnitude of the areas with the highest CMD. Applying the geophysical cross‐borehole method for estimating K‐distributions in addition to traditional methods would improve CMD‐based risk assessment and evaluation of remediation performance at contaminated sites.

Temperature-Dependent Surface Charge Accumulation for Vertical and Horizontal HVDC GIL

In this paper, the heat transfer process of DC gas-insulated transmission line (GIL) is comprehensively considered, including thermal conduction, thermal convection and thermal radiation. An electric-thermal field coupling model is established to characterize the surface charge accumulation characteristics of insulators. The temperature and insulator surface charge density distribution of a 3-D GIL model under different GIL installation ways (i.e. vertical and horizontal GIL) are obtained by finite element software. The results show that: under the identical load current, a large temperature difference (up to 5.7 °C) is shown between both surfaces of vertical GIL insulator, and the temperature on the insulator surface is distributed symmetrically along the center of the insulator. However, the temperature on both surfaces of the horizontal GIL is basically the same, but the temperature distribution varies greatly along the different radial directions of the insulator (up to 5.3 °C). By comparing the surface charge density distribution of insulators under both GIL installation ways, it is found that the surface charge density of horizontal GIL is more than 20% higher than that of vertical GIL. In addition, the volume conductivity distribution of insulator varies greatly under different GIL installation ways. The volume conductivity is positively correlated with the temperature distribution, while the normal electric field on the insulator surface is negatively correlated with volume conductivity distribution. It is hoped that this study can serve as a reference for the design and safe operation of DC GIL.

Electrical resistivity tomography (ERT) measurements during water flow in a date palm stem segment

Commercial cultivation of date palms has high economic significance, particularly in arid and hyper-arid regions. Achieving commercially viable yield of dates amid water scarcity and enforced restrictions on water use requires optimising the amount and timing of irrigation. To that end, better understanding of the temporal dynamics of the water use of date palm is of great importance. Traditionally, this can be achieved through sap flow estimates obtained using heat dissipation probes. However, such measurements lack the ability to provide information on the spatial distribution of sap flow, which is important considering that date palms transport water in the entire stem cross-section. The aim of this study is to evaluate whether electrical resistivity tomography measurements have the potential to provide information on the spatial variability of flow in date palm stems. For this, flow was induced through a stem segment that was obtained from a felled date palm tree. ERT measurements were continuously obtained throughout a cycle of flow and no-flow periods. The results showed that the mean bulk electrical conductivity varied strongly due to changes in the flow conditions. In addition, it was found that the electrical conductivity of the outflow was much higher than that of the inflow, which indicates the release of stored salt from the stem segment. Analysis of the spatial distribution of the electrical conductivity suggested that flow mainly occurred in a limited part of the cross-sectional area of the stem. Overall, it was concluded that the ERT is a promising tool to investigate the spatial variability of water flow in date palm stems.

Significantly enhanced flashover voltage of epoxy in vacuum by graded surface roughness modification

AbstractThe flashover strength of epoxy (EP) insulations in the High voltage direct current applications of future energy grids can be improved by tailoring their surface condition. This work aims to improve the DC surface flashover characteristics of EP after being treated with sandpaper of different gradings. Samples with virgin EP and homogenously modified EP considering varying surface roughness (Ra = 0.54, 3.16, 5.24, and 8.35 μm) are prepared. Different experimental characterisations, such as water contact angle, surface intrinsic conductivity, surface voltages, flashover strength, and trap distributions are conducted and evaluated to analyse the difference between virgin and treated EP. Moreover, based on the obtained experimental results of homogenously treated EP and theoretical analysis, the concept of surface functionally graded materials (SFGMs) is put forward. The flashover voltages of homogenously treated EP are augmented significantly compared to virgin EP regardless of the voltage polarity and enhanced by enhancing the surface roughness. The sample TModel‐C with SFGM design shows a 45.02% and 43.75% improvement in the negative and positive flashover voltages than that of the virgin EP. In the end, COMSOL simulations are conducted to justify the experimental findings and to analyse the difference between virgin and modified samples in terms of electric field distribution.

An information theoretic Bayesian uncertainty analysis of AEM systems over Menindee Lake, Australia

SUMMARY Long-range, active-source airborne electromagnetic (AEM) systems for near-surface conductivity imaging fall into two categories: helicopter (rotary-wing) borne or fixed-wing aircraft borne. A multitude of factors such as flying height, transmitter loop area and current, source waveforms, aerodynamic stability and data stacking times contribute to the geological resolvability of the subsurface. A comprehensive comparison of the relative merits of each system considering all such factors is difficult, but test flights over well-constrained subsurface geology with downhole induction logs are extremely useful for resolution studies. However, given the non-linear nature of the electromagnetic inverse problem, handling transmitter–receiver geometries in fixed-wing aircraft is especially challenging. As a consequence of this non-linearity, inspecting the closeness of downhole conductivities to deterministic inversion results is not sufficient for studying resolvability. A more comprehensive picture is provided by examining the variation in probability mass of the depth-wise Bayesian posterior conductivity distributions for each kind of AEM system within an information theoretic framework. For this purpose, probabilistic inversions of data must be carried out. Each acquiring system should fly over the same geology, survey noise levels must be measured and the same prior probabilities on conductivity must be used. With both synthetic models as well as real data from over the Menindee calibration range in New South Wales, Australia, we shed new light on the matter of AEM inverse model uncertainty. We do this using two information theoretic attributes derived from different Kullback–Leibler divergences—Bayesian information gain, and a strictly proper scoring rule, to assess posterior probabilities estimated by a novel Bayesian inversion scheme. The inversion marginalizes fixed-wing geometry attributes as generic nuisance parameters during Markov chain sampling. This is the first time-domain AEM study we know of, that compares nuisance marginalized subsurface posterior conductivities from a fixed-wing system, with rotary-wing derived posterior conductivities. We also compare field results with induction log data where available. Finally, we estimate the information gain in each case via a covariate shift adaptation technique that has not been used before in geophysical work. Our findings have useful implications in AEM system selection, as well as in the design of better deterministic AEM inversion algorithms.

Effect of injection water ionic strength on estimating hydraulic parameters in a 3D sand tank using silica encapsulated magnetic DNA particles

We investigated the applicability of Silica encapsulated, superparamagnetic DNA particles (SiDNAmag) in determining aquifer hydraulic parameters at different ionic strengths (1 mM, 5 mM, and 20 mM phosphate buffer) of injection suspension. Thereto, in a homogeneous, unconsolidated sand tank we pulse - injected two uniquely sequenced SiDNAmag at two injection points. At 0.5 m and 0.8 m downstream from the injection points, we measured the concentration of SiDNAmags at three vertically distributed and two horizontally distributed sampling locations. We estimated the hydraulic parameter distributions from the SiDNAmag breakthrough curves through a Monte – Carlo approach and compared the parameter distributions with salt tracer breakthrough curves. Our results indicated that at all the ionic strengths, the times of peak concentrations, and the shapes of the breakthrough curves were similar to the salt tracer. As compared to the salt, a 1 – 3 log units reduction in the maximum effluent concentration of SiDNAmag was due to kinetic attachment. The attachment rate reduced from 1 mM to 5 mM phosphate buffer possibly due to competitive adsorption of phosphate onto the favourable attachment sites. SiDNAmag attachment rate further increased in 20 mM buffer suspension, possibly due to the compression of electric double layer and reduction in energy barrier for attachment. The parameter distributions of hydraulic conductivity (k), effective porosity (ne), longitudinal dispersivity (αL), vertical transverse dispersivity (αTV /αL) and horizontal transverse dispersivity (αTH /αL) estimated from the SiDNAmag and the salt tracer breakthrough curves were statistically similar. Our work contributes to the applicability of colloidal SiDNAmags for determining hydraulic parameters at different ionic strength conditions.

Mechanisms of conductive filament formation in hafnium oxide multilayer structures

The paper describes an investigation of resistive switching in the Pt/HfO2/HfOxNy/TiN, Pt/HfO2/TaOxNy/TiN, and Pt/Al2O3/HfO2/TaOxNy/TiN structures with oxide layers deposited by atomic layer deposition. Using conductive atomic force microscopy, we demonstrate the formation of conductive filaments in every structure. We also perform a complete resistive switching cycle. We define the properties of the filaments formed at different voltages and present the size and conductivity distributions of the filaments. Our research confirms that filaments in amorphous hafnium oxide initiate on the film defects, however, defects at different materials interfaces can enhance filament density in structures with different oxide layers. It appears that among the presented structures, the Pt/Al2O3/HfO2/TaOxNy/TiN structure has the greatest potential for use in resistive random-access memory.

Reconstructing sediment distribution in meandering river deposits through a simplified numerical modelling approach, with applications to the Holocene deposits of the Venetian Plain (Italy)

Abstract Many present-day alluvial floodplains display traces of abandoned meandering channel belts developed during the past millennia (i.e. mid to late Holocene). Deposits of these ancient rivers represent preferential pathways for groundwater flows and related environmental issues, such as contaminant propagation or saltwater intrusion in coastal areas. However, since formative bankfull flows in such old and abandoned routes are hard to estimate, fossil meanders have not been commonly addressed by morphodynamic numerical models, and most of them have been investigated following classical sedimentological approaches based mainly on punctual data derived from sedimentary cores. This study aims at investigating the sediment distribution within different fossil bends on the southern Venetian Plain (NE Italy), and relating such distribution to numerically modelled bed shear stresses used herein as a proxy of sediment sorting patterns. For this purpose, formative flows in the studied palaeomeanders are first inferred from measured sediment grain size and estimates of bend widths. Then, shear stress distributions are computed along the studied palaeobends using a 2D linearized model. Model results are finally compared with conductivity distributions gauged directly in the field through electromagnetic induction investigations in the frequency domain. Our results suggest significant correlations between shear stress distributions and sediment sorting estimated from conductivity data. We deem that the integration between sedimentological reconstructions and state-of-the-art numerical modelling can provide a solid contribution to predicting the spatial distribution of sediment properties within ancient meandering channel belts, with relevant implications for the understanding of shallow aquifer dynamics and soil management.

Identifying interactions of linked irrigated lake-groundwater system by combining hydrodynamic and hydrochemical method.

During the irrigation period, the interactions between the linked lake-groundwater systems are complicated and change. This is because natural and human activities are happening at the same time, which makes it harder to identify the interactions. This study uses data on water level, hydrochemistry, and hydrogen-oxygen stable isotopes to analyze the hydrodynamics, electrical conductivity (EC), isotopic characteristics, and spatial distribution of lake water and groundwater to reveal lake-groundwater interactions. The results indicate that the hydrochemical type of Chagan Lake and groundwater is dominated by the HCO3-Na type. The key hydrochemical indicator EC obtained by principal component analysis (PCA) can be used to reveal the lake-groundwater interaction, and the interaction should be identified by location according to the significant correlation between hierarchical clustering results and regional distribution. The lake body's geographic coefficient of variation for EC and δ18O is small, and irrigation return flow is one factor in the region's surface water's significant spatial variation for EC and δ18O. The three study methods indicate that the groundwater supplies the lake in the vicinity of the Huoling River-Hongzi Pool, while in other sections, the lake water leaks and replenishes the groundwater, exhibiting geographic inconsistency. The isotope method was employed as a support tool to determine that groundwater might recharge the lake at Xinmiao Pool. According to the calculations of the Mix SIAR model, the groundwater recharge contribution rate in the Xinmiao Pool section is approximately 51%, while in the remaining sections, the contribution rate of lake water to groundwater ranges from approximately 25% to 52%. Therefore, the identification of the interaction is crucial for the linked irrigated lake-groundwater system where water sources are scarce and threatened by agricultural pollution.

Physiological-induced conductive response evaluation in specific muscle compartments under hybrid of electrical muscle stimulation and voluntary resistance training by electrical impedance tomography.

Objective: The physiological-induced conductive response has been visualised for evaluation in specific muscle compartments under hybrid (hybridEMS) of electrical muscle stimulation (EMS) and voluntary resistance training (VRT) by electrical impedance tomography (EIT). Methods: In the experiments, tendency of conductivity distribution images σ over time was clearly detected for three specific muscle compartments, which are called AM 1 compartment composed of biceps brachii muscle, AM 2 compartment composed of triceps brachii muscle, and AM 3 compartment composed of brachialis muscle, under three training modalities. Results: From the experimental results, the tendency of physiological-induced conductive response are increased in all three training modalities with increasing training time. Correspondingly, the spatial-mean conductivity <σ>AM1,AM2,AM3 increased with the conductance value G and extracellular water ratio β of right arm by bio-impedance analysis (BIA) method. In addition, hybridEMS has the greatest effect on physiological-induced conductive response in AM 1, AM 2, and AM 3. Under hybridEMS, the spatial-mean conductivity increased from <σ pre > AM1 = 0.154 to <σ 23mins > AM1 = 0.810 in AM 1 muscle compartment (n = 8, p < 0.001); <σ pre > AM2 = 0.040 to <σ 23mins > AM2 = 0.254 in AM 2 muscle compartment (n = 8, p < 0.05); <σ pre > AM3 = 0.078 to <σ 23mins > AM3 = 0.497 in AM 3 muscle compartment (n = 8, p < 0.05). Conclusion: The paired-samples t-test results of <σ>AM1,AM2,AM3 under all three training modalities suggest hybridEMS has the most efficient elicitation on physiological induced conductive response compared to VRT and EMS. The effect of EMS on deep muscle compartment (AM 3) is slower compared to VRT and hybridEMS, with a significant difference after 15min of training.

Enormously large tippers observed in southwest China: can realistic 3-D EM modeling reproduce them?

Vertical magnetic transfer functions (tippers) estimated at a global/continental net of geomagnetic observatories/sites can be used to image the electrical conductivity structure of the Earth’s crust and upper mantle (down to around 200 km). We estimated tippers at 54 geomagnetic observatories across China, aiming eventually to invert them in terms of subsurface three-dimensional (3-D) conductivity distribution. Strikingly, we obtained enormously large tippers at three inland observatories in southwest China. Large tippers are often observed at coastal/island observatories due to high conductivity contrasts between resistive bedrock and conductive seawater. However, tippers at those inland observatories appeared to be a few times larger than coastal/island tippers. As far as we know, such large tippers (reaching value 3) were never reported in any region worldwide. We perform electromagnetic simulations in 3-D conductivity models mimicking the geological setting and demonstrate that enormously large tippers are feasible and can be attributed to a current channeling effect.Graphical

NaHCO3 synergistic electrokinetics extraction of F, P, and Mn from phosphate ore flotation tailings

In this study, the NaHCO3 synergistic electrokinetic method was used to remove F, P, and Mn from phosphate ore flotation tailings (PTs). First, using PHREEQC simulation calculations, the occurrence forms of P, F, and Mn in the PTs were determined. Thereafter, under various electrokinetic treatment conditions, the variation trends between pH and the different forms of various elements in interstitial solutions of the PTs were analyzed. The influence of various electrokinetic treatment methods on conductivity and pH distribution was thoroughly investigated. The difference in P concentration between the cathode and anode chambers was 21.42 mg/L, the removal efficiency of Mn was 71.43 %, and the leaching of F was inhibited. Dissolved impurities migrated to the electrode chamber during electrokinetic treatment primarily because of electromigration and electro-osmotic flow. During the 1.00 M NaHCO3-enhanced electrokinetic treatment in the cathode chambers, in 360 min, P and F concentrations increased from 3.51 mg/L to 57.28 mg/L and 2.073 mg/L to 29.38 mg/L, respectively. Solution-precipitation of hydroxide or carbonate minerals was determined to be an important mechanism for P, F, and Mn stabilization. This study demonstrated that the NaHCO3 synergistic electrokinetic method is suitable for removing F, P, and Mn from PTs. The findings of this study provide insights for developing novel technologies for the clean treatment and high-value utilization of PTs.

In situ characterization of Ni-rich NMC811 thin films prepared by sol-gel method using different scanning probe microscopy techniques

In this paper, LiNi0.8Co0.1Mn0.1O2 (NMC811) thin films were prepared by the sol-gel method based on different parameter conditions, and the microstructure and electrochemical properties of the films were compared to obtain the film sample under the best preparation parameters. In order to explain the formation mechanism of cell battery performance based on the NMC811 cathode at the nano scale, electrochemical strain microscopy, conductive atomic force microscopy and Kelvin probe force microscopy are specifically utilized to study the changes of NMC811 thin film in electrochemical deformation, conductivity, and potential distribution under different electrical and thermal fields. The results indicate that the local amplitude, conductivity, and electrical potential of thin film in the scanning region increases with the voltage from 0 V to 3 V and the temperature from 25 °C to 150 °C. However, the electrochemical deformation, conductivity, and potential of the film decrease significantly when the voltage is applied to 4 V or the temperature rises to 200 °C.These results provide visual evidence for the influence of external field on the phase structure change and lithium-ion diffusion behavior of NMC811 thin film.

One-dimensional structure reparameterized convolutional neural network for two-phase image reconstruction based on ERT

Electrical resistance tomography (ERT) can be applied to two-phase flow pattern identification which is a key research direction for improving the operational safety of different industrial equipment systems with complex flow fields. Aiming at the existing problem that the traditional algorithm for defining flow patterns cannot accurately establish the mapping relationship between the measured voltage from ERT system and the two-phase flow conductivity distribution, a novel one-dimensional structure reparameterized convolutional neural network (1D-SRPCNN) algorithm for two-phase flow pattern image reconstruction based on ERT is proposed. First, finite element method and deep learning software framework are used to build dataset and train the neural network model respectively. Second, a deep residual network (ResNet) is used as the main network structure in the algorithm, and the one-dimensional multiscale feature extraction block (1DMSFE-Block) is improved by structural reparameterization. Then, multiscale convolution is introduced to 1DMSFE-Block for extracting features of different receptive field sizes and performing linear fusion, and the predicted two-phase flow conductivity pixel vector is obtained by the feature map passing with three fully connected layers. The results show that 1D-SRPCNN has high reconstruction performance, the average relative image error is 5.15%, the average correlation coefficient is 97.2%, and it has high anti-noise performance and generalization performance. Different experimental data also show that 1D-SRPCNN has high image reconstruction accuracy and efficiency. The research will provide important theoretical support for accurately identifying two-phase flow patterns in different fields.

Multifactor analysis of heat extraction performance of coaxial heat exchanger applied to hot dry rock resources exploration: A case study in matouying uplift, Tangshan, China

To obtain an excellent heat exchange effect, it is necessary to optimize the technical processes of single-well coaxial heat exchange. Based on numerical simulation and field investigation, this study shows that a high inlet temperature can significantly improve the outlet temperature while a low inlet temperature can obtain a high heat extraction power. The outlet temperature and heat extraction power show a positive correlation binomial relation with the inlet flow rate, the thermal conductivity of cement, the thermal conductivity of reservoir and the borehole diameter, which exhibit linear negative and positive correlation relationships with the thermal conductivity of inner tube and geothermal gradient. The inlet flow rate, geothermal gradient and thermal conductivity of the inner tube are the most significant factors, followed by the thermal conductivity of reservoir and the borehole diameter, while the inlet temperature and thermal conductivity of cement are the insignificant factors. It is recommended to select the reservoirs with high geothermal gradient, good thermal conductivity and wide stable distribution, develop fixing well cement with high thermal conductivity and inner pipe materials with excellent insulation performance, reduce the inlet temperature, increase the inlet flow rate of working fluid and expand the well diameter while considering costs.

Image reconstruction method for electrical impedance tomography based on RBF and attention mechanism

Electrical impedance tomography (EIT) is an imaging technology for estimating the conductivity change for the measured field of the human body. However, because EIT image reconstruction is severely ill-posed and nonlinear inverse problem, the reconstructed image based on traditional algorithm is lower accurate with obscure boundaries and lots of artifacts. In order to improve the accuracy of reconstructed image, an EIT image reconstruction method based on RBF and attention mechanism is proposed in this paper. The proposed RCU-Net network architecture consists of two sub-networks: RBF and CBAM-UNet. The RBF neural network accomplishes the nonlinear mapping between the boundary voltages and conductivity distribution values. The CBAM-UNet combining attention mechanism CBAM with U-Net makes further processing for the resulting images to obtain more sharp and explicit images. RCU-Net was trained and tested on the simulated dataset created by EIDORS platform. The experiment reveals that the proposed method outperforms the traditional methods in distinguishing multi-target, generalization ability and anti-interference, and it has improved the reconstructed image quality which has an average reduction of 55.09% and 26.23% on RE (Relative Error) and an increase of 14.19% and 3.08% on CC (Correlation Coefficient) respectively compared with RBF-EIT and RBF-UNet methods. In addition, the experimental data from KIT4 system can be applied to the trained network. This successful transition also demonstrates the proposed method can reconstruct more explicit images with high fidelity.

A fast approach to determine excitation eigenfrequencies for TD-EIT and FD-EIT

Electrical impedance tomography can reconstruct the complex conductivity distribution by injecting a current or voltage at a specific frequency into the target domain. The complex conductivity spectroscopy of numerous biological tissues is frequency-dependent. A suitable excitation frequency is vital to high-quality imaging over a wide frequency range. This paper investigates the relationship between the parameters of the biological tissue impedance model and the impedance spectroscopy. A frequency selection method based on the impedance spectroscopy is proposed, in which the impedance spectroscopy on a specific electrode at the domain boundary to be measured is first scanned. In TD-EIT, the difference between the target’s impedance spectroscopy and the null field is calculated, and the frequency corresponding to its extreme value is used as the excitation signal for TD-EIT. The excitation frequency in FD-EIT is the frequency corresponding to the extreme point in the target impedance spectroscopy, and we have also used this method to image the interior of the maize ear. This study provides a quick and efficient method for determining the excitation frequency for EIT, allowing researchers to find the best excitation frequency for high-quality imaging during actual measurements.

Observation of periodic structures and pseudogaps in pristine compound α-TiNCl by STM/STS and break junction methods

Scanning tunneling microscopy and spectroscopy (STM/STS) and break-junction tunnel spectroscopy (B.TTS) measurements are performed on the pristine layered α-TiNCl semiconductor (pri-TiNCl), being the precursor of superconducting nitride chlorides. The STM topography of pri-TiNCl shows basic crystal structures with the lattice periods of a0≈ 0.38 nm and b0≈ 0.31 nm, ensuring that a clean a–b surface of micro-single crystals is obtained. From the STS measurements, the averaged conductance versus voltage dependence dI/dV(V) reveals kink structures at relatively high bias voltages of |F| ∼ −50 mV and −100 mV. The spatial (r-) conductance distributions dI/dV (V, r) (dI/dV maps) proportional to those of quasiparticle local densities of states (LDOSes) exhibit the bias-independent streak structures with the period of (4.8 ± 0.2) b0, which are predominantly observed within the range of |V| &amp;lt; 95 mV. The temperature dependence of the dI/dV B.TTS spectra shows the gap structure with the energy scale of 4Σ = 180 meV vanishing at Ts ∼ 120 K. Thus, the ratio of the gap Σ to the transition temperature Ts is 2Σ/kBTs ∼ 10. Here, kB is the Boltzmann constant. Such a ratio is typical of the pseudogap features in cuprate superconductors and dielectric gap characteristics in layered chalcogenides with charge-density waves.