Rough Growth Research Articles

Microcrystalline and nanocrystalline structure of diamond films grown by MPCVD with nitrogen additions: Study of transitional synthesis conditions

This research explores the complex influence of nitrogen concentration and substrate temperature on the resultant properties of polycrystalline diamond (PCD) films grown by microwave plasma chemical vapor deposition (CVD). In particular, we investigated the growth parameters to find the exact conditions for changing the morphology of the resulting film from microcrystalline (MCD) to nanocrystalline (NCD). A series of 2 µm-thick polycrystalline diamond films was grown on Si substrates in methane-hydrogen–nitrogen gas mixtures with varied: (i) nitrogen concentration (0–2 %) and (ii) substrate temperature (700–1050 °C). Comprehensive characterization techniques, including scanning electron microscopy (SEM), micro-Raman spectroscopy, and X-ray diffraction, were employed to assess the morphological, structural, and spectroscopic properties of the films. The study reveals that even minor additions of nitrogen significantly modulate secondary nucleation, impacting both film morphology and phase composition. Furthermore, substrate temperature emerges as another critical parameter, influencing the growth kinetics and crystallite size. The comparison of the characteristics of grown PCD films allowed us to find conditions for the formation of NCD films with minimal surface roughness and maximal growth rate: nitrogen concentration [N2] ≈ 0.2–0.5 % and temperature T ≈ 850–900 °C. These findings can be used to optimize the CVD synthesis parameters of PCD films for applications as protective or friction-reducing layers, as well as for superhard cutting tools and optical devices.

Treating the Symptoms as Well as the Root Causes: How the Digital Economy Can Mitigate the Negative Impacts of Land Resource Mismatches on Urban Ecological Resilience

In the era of the digital economy (DE), the traditional economic growth paradigm is no longer applicable. To explore whether the DE can improve the urban ecological problems left behind by rough economic growth, this study examines the effects of land resource mismatch (LRM) on urban ecological resilience (UER) and evaluates the mitigating influence of the DE. This analysis utilizes data from 280 prefectural-level cities in China over the period from 2007 to 2021 and reveals that LRM significantly undermines UER, with this conclusion remaining robust across a series of tests. Additionally, the detrimental impact of LRM on UER is more pronounced in megacities, cities with high levels of economic development, and those with a lower degree of advanced industrial structure. In further analysis, this study finds that the digital economy can optimize the allocation of land resources, thereby enhancing urban ecological resilience, which has the effect of “treating the root causes”. In addition, digital government and digital infrastructure, as key elements of the digital economy, also mitigate the negative impacts of land resource misallocation on urban ecological resilience, having the effect of “treating the symptoms”. Finally, this study proposes policy suggestions such as optimizing ecological layout, deepening land reform, and promoting digital government and infrastructure construction to provide a theoretical basis and practical guidance for local governments to enhance UER and help build a new model of greener, more resilient, and sustainable urban development.

Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO2 nanocomposites and tuning the dielectric relaxation, optical, and photoluminescence performances

Nanocomposite films consisting of carboxymethyl cellulose, polyethylene oxide (CMC/PEO), and anatase titanium dioxide (TO) were produced by the use of sol-gel and solution casting techniques. TiO2 nanocrystals were effectively incorporated into CMC/PEO polymers, as shown by X-ray diffraction (XRD) and attenuated total reflectance fourier transform infrared (ATR-FTIR) analysis. The roughness growth is at high levels of TO nanocrystals (TO NCs), which means increasing active sites and defects in CMC/PEO. In differential scanning calorimetry (DSC) thermograms, the change in glass transition temperature (T g) values verifies that the polymer blend interacts with TO NCs. The increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites, as observed. The electrical properties of the CMC/PEO/TO nanocomposite undergo significant changes. The nanocomposite films exhibit a red alteration in the absorption edge as the concentration of TO NCs increases in the polymer blend. The decline in the energy gap is readily apparent as the weight percentage of TO NCs increases. The photoluminescence (PL) emission spectra indicate that the sites of the luminescence peak maximums show slight variation; peaks get wider, while their intensities decrease dramatically as the concentration of TO increases. These nanocomposite materials show potential for multifunctional applications including optoelectronics, antireflection coatings, photocatalysis, light emitting diodes, and solid polymer electrolytes.

A frequency-domain simulation method for the evolution of rail corrugation in curves

Rail corrugation remains a major problem in many railways and metros, leading to high noise and vibration levels as well as potential damage to the track and vehicle. A frequency domain simulation method is proposed for the evolution of the rail surface roughness, which can simulate the formation and development of rail corrugation in curves. A coupled vehicle-track dynamic model is established in the frequency domain to calculate the dynamic vertical and lateral wheel-rail contact forces and the associated vibration. The wheel-rail contact state is determined by using a multi-body dynamics model. The frictional-work wear model is used to calculate the roughness change caused by wheel-rail dynamic interaction. The method is verified by comparing the results with those of on-site testing on a 300 m radius curve of a metro line. It is shown that the main causes of rail corrugation are associated with the peaks in the vertical wheel-rail forces in the frequency domain, generated by the interaction between the wheel and rail. At short wavelengths the corrugation is associated with the wave reflections in the rail between adjacent axles. The phase relationship between the vertical wheel-rail force and the initial roughness has a strong influence on the roughness growth trend, leading to preferential growth in certain wavelength bands. The wheel-rail contact state and friction parameters affect the rate of development of the corrugation. Finally, a corrugation index is proposed to allow quick evaluation of the wavelength and growth rate of corrugation.

Assessing the effect of Artemisia sieberi extracts on surface roughness and candida growth of digitally processed denture acrylic materials.

Denture stomatitis, frequently encountered, is generally addressed symptomatically, with limited exploration of preventive approaches involving antifungal medicinal plants. This study assessed the impact of Artemisia sieberi extracts on the candida growth of conventional and digitally processed acrylic materials. Thirty acrylic resin discs (3 mm thickness × 10 mm diameter) were prepared by conventional or CAD/CAM technology (milling and 3D printing). The resin discs were exposed to simulated brushing, thermocycling, and immersion in Artemisia sieberi extract for 8 hours. The surface roughness of the discs was assessed at baseline and after immersion in Artemisia sieberi extract. Candida growth was quantified through colony-forming units (CFU/mL). Data was analyzed using SPSS v.22 (α⩽ 0.05). Irrespective of the material type, the post-immersion surface roughness was significantly higher compared to pre-immersion values (p< 0.05). Candida growth was significantly higher in conventional acrylic materials than digitally fabricated acrylics (p< 0.05). At × 3, Ra and CFU were found to be moderately positive and non-significantly correlated (R= 0.664, p= 0.149). At × 4, Ra and CFU were found to be weak positive and non-significantly correlated (R= 0.344, p= 0.503). Artemisia sieberi extracts had a notable impact on digitally fabricated denture acrylics, reducing candida albicans growth compared to conventional heat-cured acrylic. This suggests a potential role for these extracts in improving denture hygiene and preventing denture stomatitis, particularly in the context of digitally fabricated dentures.

Enhancing the bond strength between glass fibre reinforced polyamide 6 and aluminium through μPlasma surface modification

Thermoplastic polymers generally exhibit relatively low surface energies and this often results in limited adhesion when bonded to other materials. Plasma surface modification offers the potential to functionalise the polymer surfaces, and thereby enhance the bond strength between dissimilar materials. In this study, glass fibre reinforced polyamide 6 (GFPA6) was modified using a novel μPlasma surface treatment technique and the effectiveness of the adhesive bond with aluminium was evaluated. The treated GFPA6 surfaces were characterised using atomic force microscopy (AFM), Raman spectroscopy, contact angle measurements, surface free energy calculations and wetting envelope analysis. The results show that there was a near exponential growth in root mean square roughness with increasing treatment scans. A significant increase in carbonyl and amide functionality on the polymer surface was observed using Raman spectroscopy. The total surface energy was found to increase from 42.2 mN/m to 67.6 mN/m following a single treatment scan. Significant increases in the tensile shear strength were observed up to 10 treatment scans, going from 1 kN to 2.3 kN, but no further increase was observed with additional treatment scans. These observations, coupled with the atmospheric nature of the technique, points to great potential as a rapid, on-line, and effective, polymer surface treatment technique.

Evolution of the mixed mode FPZ and fracture roughness of Beishan granite after coupled thermo-hydro-mechanical treatment

Deep surrounding rocks contain a network of longitudinally intersecting fissures. Exploration of their fracture process zone (FPZ) size evolution during mixed loading and fracture surface roughness after failure has always been a hot topic, especially for coupled thermo–hydro–mechanical (THM) treatment. This study takes Beishan granite as the research object. The fracture surface roughness and FPZ length were obtained using Grasselli statistical and mixed strain–displacement methods. Finally, an electron microscope was employed to observe the fracture surface after failure at different temperatures and loading angles. Results reveal a notable temperature and load dependence of the fracture surface roughness and FPZ length evolution. In the low-temperature stage (25°C–300°C), the mineral primarily exhibited transgranular fractures and the average fracture surface roughness showed a slightly decrease with increasing temperature. In the high-temperature stage (500℃–650℃), the degree of internal damage to the prepared specimens substantially increased, with intergranular fractures being the dominant fracture mode, and rapid roughness growth occurred. Under the same temperature condition, the roughness value was in the order of mode I > mixed mode > mode II. The FPZ length increased, stabilized, and decreased as the load increased. In the low-temperature stage, the FPZ length reached its maximum value at the maximum load, whereas in the high-temperature stage, the FPZ length was fully developed before the peak load. Under the same loading angle condition, the FPZ lengths corresponding to the three loading modes followed the order of mode I < mixed mode < mode II.

Statistical Analysis of the Surface Roughness on Aircraft Icing

A statistical analysis of the surface roughness is performed on experimentally obtained ice shapes on an asymmetrical airfoil at Rec≈2⋅106. The ice shapes were generated in the Icing Wind Tunnel of the Technical University of Braunschweig under Appendix C and O conditions of the EASA airplane certification standards as part of the ICE GENESIS project. The photogrammetry method is used for the digitization of the experimental ice shapes, while statistical parameters such as the mean ice shape and the local root mean square (RMS) of the ice geometry are extracted using a traditional surface projection method, as well as a self-organizing maps approach. Results show the evolution of the statistical parameters over time and the influence of the freestream static temperature on these parameters. A comparison between the experimental values of the local RMS of the ice geometry and a correlation for roughness prediction is presented, showing a good match with the original formulation of the correlation for cases under Appendix C conditions while having a good match with Appendix O conditions when a temperature correction factor is applied to the formulation. Additionally, results show an almost linear growth of roughness over the whole accretion time.

Morphology, phase composition, surface roughness evolution and growth mechanism of hot-dip aluminum coating on Mo substrate

The Al-rich hot-dip aluminum composite coatings were synthesized on Mo surface by hot-dip aluminizing under different deposition processes. The aluminide coatings present a very smooth dense coating structure with a lower surface roughness and fine grain size, the average surface roughness (RSa) values are only 0.118–0.869 μm, and the corresponding surface area growth rate (Sdr) values are 3.85–80.19 %. Increasing the deposition temperature is beneficial for the transition of low melting point compounds of the coating surface to high melting point compounds, and extending the hot dip time is profit for the diffusion and enrichment of Al atoms on the coating surface. Besides, increasing the deposition temperature or time can also promote the growth of Al4Mo grains, thereby significantly increasing the coating thickness. When the deposition temperature is 750 °C, the thicknesses of Al4Mo and Al8Mo3 layers increases in a parabolic law with deposition time, and the Kp values both of them are 3.46 × 10−13 m2/s and 1.47 × 10−15 m2/s, respectively. The growth of the coating depends on the continuous diffusion of Al atoms towards the substrate direction, and the difference in chemical potential between Al atoms in each phase is the main driving force for coating growth.

Investigation of structural and optical properties of Mg doped ZnS thin films prepared by Mist-CVD technique: Experimental and theoretical aspects

In the present study, undoped and magnesium (Mg)-doped zinc sulfide (ZnS) thin films were prepared using the low-cost Mist CVD technique on a soda-lime glass substrate in a reactor chamber maintained at a high temperature of 450 °C ± 10 °C. The structural, vibrational, chemical compositional, morphological, optical and electric characteristics of the prepared Zn1-xMgxS thin films were studied using X-ray diffraction (XRD), Raman spectroscopy, energy dispersive spectrometer (EDS), scanning electron microscopy (SEM), photoluminescence emission (PL), atomic force microscopy (AFM) analysis, and Hall effect measurements. The aim of the present work is to examine the effect of incorporation of Mg into ZnS thin films matrix. XRD and Raman spectroscopy investigations confirmed the formation of polycrystalline micro structured films. The presence of Zn, S, and Mg elements was confirmed by EDS Analysis. The growth of the surface roughness of the films with increasing Mg content, as well as the crystalline size lead to a higher carrier concentration (5.103 × 1018 cm−3), and lower resistivity of the thin films (5.021 × 10−3 Ω cm). Furthermore, DFT investigation of the electronic properties using the GGA/PBE + U functional provides a detailed explanation of the band structure and confirms the band gap reduction after doping wurtzite ZnS with Mg (12 at.%). Therefore, the outcome of this of this study might provide an experimental and theoretical background for future research on Mg-doped ZnS.

Silencing essential gene expression in Mycobacterium abscessus during infection.

Mycobacterium abscessus is a multi-drug-resistant non-tuberculous mycobacterial species causing tuberculosis-like lung infections. The functional characterization of the extensive repertoire of genes encoding virulence factors and drug targets has been largely restricted by the lack of powerful genetic tools. In this study, we evaluated the performances of a Tet-OFF system, previously optimized for M. tuberculosis and M. smegmatis. Fluorescence reporter M. abscessus strains were developed where mCherry was under the control of the Tet-OFF regulatory system on an integrative plasmid. The addition of anhydrotetracycline (ATc) correlated with a decrease in fluorescence intensity not only in solid and broth medium but also in colony biofilms, for both smooth and rough variants of M. abscessus. Next, unmarked mmpL3 conditional knockdown mutants were engineered in both smooth and rough M. abscessus. Biochemical studies indicated that the addition of ATc was associated with a dose-dependent decrease in (i) the production of the MmpL3 protein, (ii) the biosynthesis of trehalose dimycolate and mycolylated arabinogalactan, (iii) bacterial viability on agar and liquid medium as well as in biofilms. Importantly, intravenous injection of ATc in zebrafish embryos infected with the rough mmpL3 conditional mutant impeded bacterial growth and correlated with a significant gain in embryo survival. These results suggest that mmpL3 is essential for M. abscessus growth in vitro and in the infected host, thus validating MmpL3 as an attractive drug target. Together, this study demonstrates the potential of ATc-dependent repression to modulate the expression of M. abscessus genes in the infected host. IMPORTANCE Mycobacterium abscessus represents the most common rapidly growing mycobacterial pathogen in cystic fibrosis and is extremely difficult to eradicate. Essential genes are required for growth, often participate in pathogenesis, and encode valid drug targets for further chemotherapeutic developments. However, assessing the function of essential genes in M. abscessus remains challenging due to the limited spectrum of efficient genetic tools. Herein, we generated a Tet-OFF-based system allowing to knock down the expression of mmpL3, encoding the mycolic acid transporter in mycobacteria. Using this conditional mutant, we confirm the essentiality of mmpL3 in planktonic cultures, in biofilms, and during infection in zebrafish embryos. Thus, in this study, we developed a robust and reliable method to silence the expression of any M. abscessus gene during host infection.

Land use evaluation considering soil properties and agricultural infrastructure in black soil region

AbstractSystematic assessment of arable land use is a fundamental prerequisite to explore its sustainable development path. Agricultural infrastructure integrated with the tillage conditions and soil properties was used to evaluate the state of regional arable land use and its potential for sustainable productivity. We propose a combined weighting method integrating Delphi and entropy weights to consider both decision objectives and indicator attributes. The proposed approach takes into account both expertise and data feature, making the evaluating results more rational and applicable. The impacts of large‐scale land use change and regional urban distribution on soil properties and agricultural infrastructure were also explored to develop more rational and differentiated conservation strategies. Our evaluation showed that 44% and 48% of the soil properties of arable land in Heilongjiang Province, China, are in the excellent or good grades, respectively, meaning that no or only minor remediation measures are needed to achieve optimum conditions. Agricultural infrastructure deserves more attention from the management than soil properties, as only 16% and 24% of area have the same excellent and good grades. The results of the evaluation with a combination of subjective and objective weights are closer to a normal distribution curve than if only expert weights are used, which confirms our hypothesis that the new weighting method is more reasonable. The newly proposed weighted design method and index provide a better understanding of the sustainable productivity of agricultural areas and have a promising application in large‐scale black soil areas worldwide. The future rough growth strategy for resources will result in degradation and posed risks to regional ecological conservation. At the provincial level (up to 130 km), agricultural infrastructure declines and then rises as fields move away from cities, with the inflection point at 55 km. State‐owned farms are mainly responsible for this inflection point, which shift the agents of arable land from small farmers to large capital, with remote arable land receiving more investment. The impact mechanisms of urbanization should be deeper explored to address the challenges for arable land conservation.

Nanoscale Investigation of Bubble Nucleation and Boiling on Random Rough Surfaces.

Surface roughness is one of the significant factors affecting liquid-vapor phase change heat transfer. This paper explores the effect of surface roughness on bubble nucleation and boiling heat transfer, as well as the microscopic mechanism, by constructing random rough surfaces using molecular dynamics (MD) simulation. Bubbles randomly nucleate on a flat surface and tend to nucleate in pits on rough surfaces. The pits on the random rough surface gather more argon atoms than the protrusions, forming low potential energy regions on the surface, thus providing stable nucleation sites for bubbles. As the surface roughness increases, bubble generation, merging, and growth are advanced. In addition, rough surfaces offer a larger effective heat transfer area for the heat transfer process, increase the strength of solid-liquid coupling, and obtain smaller solid-liquid interaction energy. The critical heat flux (CHF) value positively correlates with surface roughness. As the roughness increases, the surface superheat at the onset of CHF decreases accordingly. This paper provides new insights into the mechanism of heat transfer enhancement on rough surfaces and surface design in thermal management.

Effect of the thermally grown oxide and interfacial roughness on stress distribution in environmental barrier coatings

To clarify the role of interface morphology and thermally grown oxide (TGO) in the failure of environmental barrier coatings (EBCs). In this study, the effect of chemical expansion on free energy was considered based on the continuous thermodynamic framework. The effects of roughness and TGO growth on the stress distribution of EBCs were investigated. The results showed that the stress coupling effect led to the inhomogeneous growth of TGO by affecting the gas diffusion and gas inflow rate. The TGO thickness at the peak increased with increasing roughness, and the TGO thickness at the valley and the middle position decreased with increasing roughness. The y-direction at the TGO/EBC valley and the TGO/BC peak under tensile stress increased with the TGO thickness and roughness and may be the first to fail in delamination. The calculation results of the model can provide a theoretical basis for the coating design and manufacturing process.

USE OF APAMARGA KSHARSUTRA IN THE MANAGEMENT OF WART (CHARMAKEELA): A CASE STUDY

Introduction: Warts, also known as Verrucae, is a common dermatological condition caused by Human Papilloma Virus (HPV). A wart is generally a small, rough growth typically on human hands or feet but often in other locations that can resemble a cauliflower or a solid blister. According to Ayurveda, this ailment can be compared with Charmakeela, one of the kshudrarogas. Case presentation: A 65-year-old male patient visited OPD complaining of pedunculated growth over the left thigh region, occasionally feeling itching and discomfort at the growth site. Routine blood and urine examination were done and found within normal range. Diagnosis and management: Based on clinical features, the case was diagnosed as a wart (Charmakeela) and suggested for a Ksharasutra ligation procedure on an OPD basis. Treatment aims to destruct hyperkeratotic overgrown skin and to avoid recurrence. Outcome: There was marked improvement in the wart after Ksharasutra ligation; gradually, the wart detached from its base, leaving a minimal scar. Discussion: Satisfactory results were obtained. This case highlights that Ksharasutra ligation is a very effective and invasive procedure and one of the potential treatments for managing warts.

Effect of CdSSe nanoparticles on the structural, surface roughness, linear, and nonlinear optical parameters of polyvinyl chloride films for optoelectronic applications

Polyvinyl chloride (PVC) was used as a host matrix for different CdSSe nanoparticles (NPs) concentrations. PVC-CdSSe films were prepared by the solution-cast method, and CdSSe NPs were prepared by the hot-injection method. A scanning electron microscope attached to an EDX unit was used to identify CdSSe elements. The reinforcement of CdSSe NPs in the PVC matrix exhibits growth in CdSSe particle size due to agglomerations. PVC-CdSSe films were examined via XRD, FT-IR, and a polarized optical microscope. The roughness tester was used to measure the surface roughness parameters of the PVC-CdSSe films, which revealed the growth in film roughness with increasing the CdSSe concentration. The UV-visible spectrophotometer was used to analyze the PVC-CdSSe film’s transmission and absorption. Tauc’s model was used to evaluate the optical bandgap (Eg). The Eg was lessened from 5.45 eV for pure PVC to 4.78 eV for PVC-3wt%CdSSe film, while the Urbach energy was increased upon CdSSe NPs additive to the PVC matrix testifying to the formation of the localized states with high-density. Furthermore, an improvement in nonlinear optical parameters (estimated via the Wemple-DiDomenico model) was observed. The third-order nonlinear optical susceptibility ( χ(3)) enhanced from 4.08 × 10−15 for pure PVC to 1.91 × 10−13 for PVC-3wt%CdSSe, due to the surface plasmon oscillation of CdSSe NPs in the PVC matrix. In view of the improved optical parameters, the as-prepared PVC-CdSSe films make them a possible nominee for nonlinear optical devices.

Unravelling crystal growth of nanoparticles.

Crystal growth from nanoscale constituents is a ubiquitous phenomenon in biology, geology and materials science. Numerous studies have focused on understanding the onset of nucleation and on producing high-quality crystals by empirically sampling constituents with different attributes and varying the growth conditions. However, the kinetics of post-nucleation growth processes, an important determinant of crystal morphology and properties, have remained underexplored due to experimental challenges associated with real-space imaging at the nanoscale. Here we report the imaging of the crystal growth of nanoparticles of different shapes using liquid-phase transmission electron microscopy, resolving both lateral and perpendicular growth of crystal layers by tracking individual nanoparticles. We observe that these nanoscale systems exhibit layer-by-layer growth, typical of atomic crystallization, as well as rough growth prevalent in colloidal systems. Surprisingly, the lateral and perpendicular growth modes can be independently controlled, resulting in two mixed crystallization modes that, until now, have received only scant attention. Combining analytical considerations with molecular dynamics and kinetic Monte Carlo simulations, we develop a comprehensive framework for our observations, which are fundamentally determined by the size and shape of the building blocks. These insights unify the understanding of crystal growth across four orders of magnitude in particle size and suggest novel pathways to crystal engineering.

Microstructure and oxidation resistant of Si–NbSi2 coating on Nb substrate at 800°C and 1000°C

The Si–NbSi2 composite coating with a smooth surface was successfully prepared on Nb substrate by hot dip silicon-plating (HDS) technology. The composite coating is composed of Si outer layer, NbSi2 interlayer and Nb5Si3 interfacial layer. And the average surface roughness (RSa) and specific surface area growth rate (Sdr) are only 0.275 μm and 2.85%, respectively. The cyclic oxidation test shows that the Si–NbSi2 composite coating has a very excellent oxidative resistance after oxidation at 800 °C for different times. After oxidation for 40 h, the Δm/S and oxide layer thickness of the coating are only 3.72 mg/cm2 and 8 μm, respectively. After oxidation at 1000 °C for 20 h, the coating surface is almost completely covered by a dense SiO2 layer, the Δm/S and oxide layer thickness of the coating are 7.28 mg/cm2 and 15 μm, respectively. The Si–NbSi2 composite coating presents good self-healing ability and excellent oxidation resistance, which can significantly prolong the service life of bare Nb in oxidation environment.

Astronomically controlled deep-sea life in the Late Cretaceous reconstructed from ultra-high-resolution inoceramid shell archives.

The periodicity of the mutual position of celestial bodies in the Earth-Moon-Sun system is crucial to the functioning of life on Earth. Biological rhythms affect most of the processes inside organisms, and some can be recorded in skeletal remains, allowing one to reconstruct the cycles that occur in nature deep in time. In the present study, we have used ultra-high-resolution elemental ratio scans of Mg/Ca, Sr/Ca and Mn/Ca from the fossil, ca. 70 Ma old inoceramid bivalve Inoceramus (Platyceramus) salisburgensis from deep aphotic water and identified a clear regularity of repetition of the geochemical signal every of ~0.006 mm. We estimate that the shell accretion rate is on average ~0.4cm of shell thickness per lunar year. Visible light-dark lamination, interpreted as a seasonal signal corresponding to the semilunar-related cycle, gives a rough shell age estimate and growth rate for this large bivalve species supported by a dual feeding strategy. We recognize a biological clock that follows either a semilunar (model A) or a tidal (model B) cycle. This cycle of tidal dominance seems to fit better considering the biological behaviour of I. (P.) salisburgensis, including the estimated age and growth rate of the studied specimens. We interpret that the major control in such deep-sea environment, well below the photic zone and storm wave base, was due to barotropic tidal forces, thus changing the water pressure.

Progress of Research on Urban Growth Boundary and Its Implications in Chinese Studies Based on Bibliometric Analysis.

Urban sprawl is a development theme of cities all over the world, especially in developing countries with rapid urbanization, and the long-established rough and outward urban growth pattern has brought about a series of social and ecological problems. As an important tool in controlling urban sprawl in western countries, the urban growth boundary (UGB) has become one of the three major policy tools in the national spatial planning system since it was introduced into China. Combined with a bibliometric analysis, this literature review summarizes UGB studies on development and evolution, delimitation means, and implementation management and provides references for studying UGB adaptability in China. The results show that: (1) Originating from Howard's garden city concept, UGB studies have formed a relatively complete system of "theoretical basis, technical methods, supporting policies, and implementation management" through long-term empirical research in foreign countries. With a relatively late start in China, UGB research currently focuses on different situations between China and abroad and the adaptation of China's localization. (2) UGB delimitation mainly includes two aspects: forward expansion, which, from the urban development perspective, is mainly supported by cellular automata (CA) urban growth simulation; and reverse restriction, which, from the ecological protection perspective, is supported by ecological security pattern construction, ecological sensitivity evaluation, and land suitability evaluation. (3) Many foreign UGB implementations have different forms and more flexible and comprehensive corresponding supporting policies. However, the current state of research in China in this area is still insufficient. Against the background of the national spatial planning system reform, the findings of this review provide references for delineating UGB that considers ecological protection and urban development under the scenarios of planning, formulating a supporting mechanism for multi-subject participation and multi-party coordination, and establishing an adjustment system based on implementation effect evaluation.