Super-stable mineralization of Cu, Cd, Zn and Pb by CaAl-layered double hydroxide: Performance, mechanism, and large-scale application in agriculture soil remediation.

The synthesized CaAl-layered double hydroxide (CaAl-LDH) shows excellent performance in potentially toxic metals (PTMs) removal, and the removal capacity of CaAl-LDH toward Cu2+, Zn2+ and Pb2+ in aqueous solution is 502.4, 315.2 and 600.0 mg/g respectively. Cu2+ and Zn2+ are removed through isomorphic substitution of laminate Ca and dissolution-reprecipitation, leading to the formation of CuAl-LDH and ZnAl-LDH mineralization products. Pb2+ is removed by the complexation and precipitation to form Pb3(CO3)2(OH)2. The application of CaAl-LDH in laboratory-scale soil remediation shows that target PTMs are gradually mineralized into relatively stable oxidizable and residual state, and the immobilization efficiency of available Cu, Zn, Cd and Pb reaches 84.62 %, 98.66 %, 96.81 % and 70.27 % respectively. In addition, practical application in farmland results in the significant reduction of available Cu, Zn, Cd and Pb with the immobilization efficiency of 30.15 %, 67.30 % and 57.80 % and 38.71 % respectively. Owing to the super-stable mineralization effect of CaAl-LDH, the content of PTMs in the roots, stems and grains of cultivated buckwheat also decreases obviously, and the growth and yield of buckwheat are not adversely affected but improved. The above prove that the super-stable mineralization based on CaAl-LDH is a promising scheme for the remediation of PTMs contaminated agriculture soil.

A high-performance Cu-Al dual-ion battery realized by high-concentration Cl- electrolyte and CuS cathode.

We propose a new Cu-Al dual-ion battery that aqueous solution composed of LiCl, CuCl and AlCl3 (LiCuAl) is used as the electrolyte, CuS is used as the cathode of aqueous aluminum ion battery for the first time and copper foil is used as the anode. The assembled Cu-Al dual-ion battery yields a reversible capacity of 538 mA h/g at 200 mA/g, and exhibits longterm cycling stability of over 200 cycles with 88.6% capacity retention at 1000 mA/g. Above excellent performance is inseparable from the three components of LiCuAl electrolyte and electrode materials. The Al-storage mechanism of CuS is proposed that the S-S bond in CuS lattice interacts with aluminum ions during the aluminum storage process. In addition, the charging and discharging process does not cause irreversible damage to the S-S bond, thus Cu-Al dual-ion battery with CuS as cathode shows great cycle stability.

Activated MoS2 by Constructing Single Atomic Cation Vacancies for Accelerated Hydrogen Evolution Reaction.

Regulating the electronic structure of MoS2 by constructing cationic vacancies is an effective method to activate and improve its intrinsic properties. Herein, we synthesize the MoS2-based composite with abundant single atomic Mo cation vacancies through uniformly loading nickel-cobalt-Prussian blue analogues (NiCoPBA) (NiCoPBA-MoS2-VMo) by immersing a single Ni atom-decorated MoS2 (Ni-MoS2) into K3[Co(CN)6] solution. Subsequently, NiCoP-MoS2-VMo with improved conductivity is obtained by phosphating the composite as a high-efficiency hydrogen evolution reaction (HER) catalyst. Experiments and theoretical calculations indicate that the electrons of NiCoP are spontaneously transferred to the substrate MoS2-VMo nanosheets in NiCoP-MoS2-VMo, and the moderately oxidized NiCoP is beneficial to the adsorption of OH*. Meanwhile, the mono-atomic Mo cation vacancies of the catalyst modulate the electronic structure of S, optimizing the adsorption of hydrogen in the reaction process. Therefore, NiCoP-MoS2-VMo has enhanced chemical adsorption for H* (on MoS2-VMo) and OH*(on NiCoP), expediting the water-splitting step and HER catalysis, and benefiting from the regulation of the electronic structure induced by the construction of metallic Mo vacancies in MoS2, the as-prepared catalyst displays an overpotential of only 67 mV at 10 mA cm-2 with long-term stability (no current decay over 20 h). This work affords not only a kind of efficient HER catalysts but also a new valuable route for developing inexpensive and high-performance catalysts with single atomic cation vacancies.

Enhanced improvement of soda saline-alkali soil by in-situ formation of super-stable mineralization structure based on CaFe layered double hydroxide and its large-scale application.

In-situ super-stable mineralization technology with mineralizers (CaSO4, Fe2(SO4)3) and attapulgite (ATP) clay were applied to improve soda saline-alkali soil. The addition of mineralizers and the existence of OH and CO32- in soil resulted in the formation of CaFe-layered double hydroxide (CaFe-LDH) with super-stable mineralization structure (Ksp = 1.512 × 10-61), which was confirmed by the characterization of physicochemical properties and density functional theory (DFT) calculation. The fixation of OH- and CO32- during the formation process of CaFe-LDH led to the transformation of the existing forms of OH- and CO32- in soil from free to stable state, resulting in the permanent decrease of soil pH and CO32- concentration. The effect of ATP clay on the decrease of soluble Na ions in soil through electrostatic attraction and cation exchange was also indicated. Furthermore, mineralizers (1.2 t/ha CaSO4 and 0.75 t/ha Fe2(SO4)3) and ATP clay (1.2 t/ha) were applied to 1.33 ha soda saline-alkali land, and Rumex patientia L. was seeded meanwhile for the identification of improved performance. After five months of improvement, the physical and chemical properties of soil were improved that pH, electrical conductivity (EC), the concentration of CO32- and soluble Na ions, and soil bulk density decreased significantly. In addition, the emergence rate of Rumex patientia L. increased from 0% to 98.3%. All above indicated that in-situ super-stable mineralization technology with the properties of high efficiency, long-term and cost-effective (234.88 $/ha) displays excellent potential in the improvement of soda saline-alkali soil.

The local-neighborhood effect of green credit on green economy: a spatial econometric investigation.

Green credit is one of the most important financial instruments to promote sustainable development. Taking the provincial panel dataset of China as the research sample, this paper investigates the spatial impacts of green credit on the green economy. The super slack-based measure (Sup-SBM) model with undesirable outputs is employed to calculate the level of green economy within China. On this basis, we establish spatial Durbin models to study the impact of green credit on green economy and its transmission mechanisms. The results show that green credit exhibits a local-neighborhood effect on green economy; that is, the green credit can not only improve the local green economy but also generate spatial spillover effect to promote the development of green economy in surrounding areas. The above conclusion still holds after the robustness test by replacing spatial weight matrices and alternative measurement for the explained variable. Furthermore, enhancing innovation efficiency and optimizing energy structure are important ways for green credit to promote green economy. The findings of this study not only provide a new perspective for understanding the economic consequences of green credit policy but also provide empirical evidence for the important role of green finance in achieving the win-win goals of economic growth and environmental protection.

Acid-Etched Co3O4 Nanoparticles on Nickel Foam: The Highly Reactive (311) Facet and Enriched Defects for Boosting Methanol Oxidation Electrocatalysis.

The confirmation and regulation of active sites are particularly critical for the design of methanol oxidation reaction (MOR) catalysts. Here, an acid etching method for facet control combined with defect construction was utilized to synthesize Co3O4 nanoparticles on nickel foam for preferentially exposing the (311) facet with enriched oxygen vacancies (VO). The acid-leached oxides exhibited superior MOR activity with a mass activity of 710.94 mA mg-1 and an area-specific activity of 3.390 mA cm-2 as a result of (i) abundant active sites for MOR promoted by VO along with the highly active (311) facet being exposed and (ii) phase purification-reduced adsorption energy (Eads) of methanol molecules. Ex situ X-ray photoelectron spectroscopy proved that highly active CoOOH obtained via the activation of plentiful Co2+ effectively improved the MOR. Density functional theory calculations confirmed that the selective exposed (311) facet has the lowest Eads for CH3OH molecules. This work puts forward acid etching as the facet modification and defect engineer for nanostructured non-noble catalysts, which is expected to result in superior electrochemical performance required for advanced alkaline direct methanol fuel cells.

Heterostructure Ni3S4-MoS2 with interfacial electron redistribution used for enhancing hydrogen evolution.

Developing highly effective and inexpensive electrocatalysts for hydrogen evolution reaction (HER), particularly in a water-alkaline electrolyzer, are crucial to large-scale industrialization. The earth-abundant molybdenum disulfide (MoS2) is an ideal electrocatalyst in acidic media but suffers from a high overpotential in alkaline solution. Herein, nanospherical heterostructure Ni3S4-MoS2 was obtained via a one-pot synthesis method, in which Ni3S4 was uniformly integrated with MoS2 ultrathin nanosheets. There were abundant heterojunctions in the as-synthesized catalyst, which were verified by X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). The structure features with interfacial electron redistribution was proved by XPS and density functional theory (DFT) calculations, which offered several advantages to promote the HER activity of MoS2, including increased specific surface area, exposed abundant active edge sites and improved electron transfer. Ni3S4-MoS2 exhibited a low overpotential of 116 mV at 10 mA cm-2 in an alkaline solution with a corresponding Tafel slope of 81 mV dec-1 and long-term stability of over 20 h. DFT simulations indicated that the synergistic effects in the system with the chemisorption of H on the (002) plane of MoS2 and OH on the (311) plane of Ni3S4 accelerated the rate-determining water dissociation steps of HER. This study provides a valuable route for the design and synthesis of inexpensive and efficient HER electrocatalyst, heterostructure Ni3S4-MoS2.

Iron-containing palygorskite clay as Fenton reagent for the catalytic degradation of phenol in water.

Heterogeneous Fenton systems have great application prospects in the catalytic degradation of organic wastewater; however, they are still not widely used in operation due to the difficulty of preparing catalysts in low yields and the high manufacturing cost. Herein, we report that a pristine iron-containing palygorskite clay can be used as a Fenton catalyst reagent without any retreatment. The composition, morphology, and structure of palygorskite clay, as well as the distribution and content of Fe element in palygorskite, were characterized via several physicochemical techniques. The degradation reaction of phenol in water was carried out as a probe reaction for the palygorskite Fenton reagent. The effects of the palygorskite content, pH value, and hydrogen peroxide concentration on the degradation efficiency of phenol were studied. Under optimum operating conditions, the chemical oxygen demand (COD) degradation efficiency of phenol reaches 94% with a reaction temperature of 20 °C and a reaction time of 15 min.

Green Credit, Financial Constraint, and Capital Investment: Evidence from China's Energy-intensive Enterprises.

The green credit policy is an important green financial tool that can achieve the win-win scenario with economic development and environmental protection through the reasonable allocation of credit resources. Using the green credit guidelines (GCGs) in China as a quasi-natural experiment, this study explored the impacts of the green credit policy on the capital investment of energy-intensive enterprises in a difference-in-differences framework and established the mediation effect model to analyze the mechanisms. The empirical results showed that the capital investment of energy-intensive enterprises was significantly reduced after the promulgation of the GCGs. Considering the intermediary paths along with the green credit policy on energy-intensive investment through financial constraints, the total bank loans and long-term bank loans played partial intermediary roles, whereas the short-term bank loans as mediator variable showed no significant intermediary effect. The findings of this study illustrated that the green credit policy has been well implemented and promoted in China. It inhibited energy-intensive investment, which is of great significance to improving the efficiency of resource utilization and promoting green and low-carbon development.

The Principle of Introducing Halogen Ions Into ß-FeOOH: Controlling Electronic Structure and Electrochemical Performance.

Coordination tuning electronic structure of host materials is a quite effective strategy for activating and improving the intrinsic properties. Herein, halogen anion (X-)-incorporated ß-FeOOH (ß-FeOOH(X), X = F-, Cl-, and Br-) was investigated with a spontaneous adsorption process, which realized a great improvement of supercapacitor performances by adjusting the coordination geometry. Experiments coupled with theoretical calculations demonstrated that the change of Fe-O bond length and structural distortion of ß-FeOOH, which is rooted in halogen ions embedment, led to the relatively narrow band gap. Because of the strong electronegativity of X-, the Fe element in ß-FeOOH(X)s presented the unexpected high valence state (3 + δ), which is facilitating to adsorb SO32- species. Consequently, the designed ß-FeOOH(X)s exhibited the good electric conductivity and enhanced the contact between electrode and electrolyte. When used as a negative electrode, the ß-FeOOH(F) showed the excellent specific capacity of 391.9 F g-1 at 1 A g-1 current density, almost tenfold improvement compared with initial ß-FeOOH, with the superior rate capacity and cyclic stability. This combinational design principle of electronic structure and electrochemical performances provides a promising way to develop advanced electrode materials for supercapacitor.

Enhancing Photocatalytic Activity of Nb2O5-x for Aerobic Oxidation Through Synergy of Oxygen Vacancy and Porosity.

A major reduction in energy consumption and the costs of catalysts will be required in future chemical manufacturing processes. To reach this goal, the transitional metal oxides (TMOs) as photocatalysts under solar energy have been widely studied. Nb2O5, as a promising photocatalyst, has attracted increasing attention owing to their unique properties. However, the intrinsic large bandgap of Nb2O5 hinder its potential applications in a variety of fields. Herein, we report an effective and simple strategy to synthesize black mesoporous Nb2O5-x nanorods (BMNb) with abundant oxygen vacancies. The formation of oxygen vacancy reduces the bandgap of Nb2O5 which extend the photoresponse from the ultraviolet to the visible and infrared light regions. In addition, The mesoporous structure of BMNb lead to a higher surface area than the as-prepared Nb2O5 precursor (36.24 m²/g cf 8.69 m²/g). Benefitting from coordinated regulation of structure and composition, the BMNb exhibits better photocatalytic performance than Nb2O5 in aerobic oxidative coupling of amines to imines under visible light irradiation at room temperature. The yield of BMNb for benzylamine oxidation increases by 63% over the Nb2O5. This work could open new perspectives to design TMOs with enhanced photocatalytic properties.

A hierarchical Nb2O5@NiFe-MMO rod array, fabricated and used as a structured photocatalyst.

Recently, using sunlight as a driving force with transitional metal oxides as photocatalysts, due to their unique optical and catalytic properties for organic reactions, has been considered to be a promising strategy in synthetic chemistry. Here, a hierarchically structured photocatalyst, a NiFe mixed metal oxide coated Nb2O5 (denoted as Nb2O5@NiFe-MMO) rod array has been successfully fabricated using Nb foil as a substrate. The Nb2O5 rod array was synthesized by the oxidative etching of Nb metal on the surface of the a substrate. The coating NiFe-MMO was obtained by the calcination of a NiFe layered double hydroxide (NiFe-LDH) precursor via the in situ epitaxial growing technique. The Nb2O5@NiFe-MMO rod array extended the photoresponse light region from ultraviolet light around 400 nm to visible light around 600 nm. With the well-designed architecture and highly dispersed NiO and Fe2O3, the as-prepared photocatalyst exhibited excellent activity and recyclability toward the reaction of aerobic coupling under relatively green conditions, with catalytic efficiency of 228 µmol cm-2 (the area is that of the Ni foil substrate) at 30 °C for 5 h. The present work provides a new strategy for the exploration of excellent structured photocatalysts based on transition metal oxide materials for selective aerobic oxidation of benzylamine to imine.

Enrichment of rare earth metal ions by the highly selective adsorption of phytate intercalated layered double hydroxide.

Phytate intercalated MgAl layered double hydroxide (MgAl-LDH) was prepared by an anion exchange method with the precursor NO3- containing MgAl-LDH. The final as-synthesized product [Mg0.69Al0.31(OH)2] (phytateNa6)0.05 (NO3)0.01·mH2O (phytate-LDH) has highly selective adsorption ability for some metal ions and can be used to enrich rare earth metal ions in mixed solution, such as Pr3+ and Ce3+ from a mixed solution of them with Pb2+ and Co2+. At first, phytate-LDH has good adsorption performance for these ions in single metal ion solutions. At low concentration (below 10 mg L-1), all the capture rates of the four metal ions were more than 97%, for highly toxic Pb2+ it was even up to nearly 100%, and a high capture rate (99.87%) was maintained for Pb2+ at a high concentration (100 mg L-1). When all the four metal ions are co-existing in aqueous solution, the selectivity order is Pb2+ ≫ Pr3+ ≈ Ce3+ > Co2+. In a solution containing mixtures of the three metal ions of Pr3+, Ce3+, and Co2+, the selectivity order is Pr3+ ≈ Ce3+ ≫ Co2+, and in a solution containing mixtures of Pr3+ with Co2+ and Ce3+ with Co2+, the selectivity orders are Pr3+ ≫ Co2+ and Ce3+ ≫ Co2+, respectively. The high selectivity and adsorption capacities for Pb2+, Co2+, Pr3+, and Ce3+ result in the efficient removal of Pb2+ and enrichment of the rare earth metal ions Pr3+ and Ce3+ by phytate-LDH. Based on the elemental analysis, it is found that the difference of the adsorption capacities is mainly due to the different coordination number of them with phytate-LDH. With molecular simulation, we believe that the adsorption selectivity is due to the difference of the binding energy between the metal ion and phytate-LDH. Therefore, the phytate-LDH is promising for the enrichment and/or purification of the rare earth metal ions and removal of toxic metal ions from waste water.

Formaldehyde regulates vascular tensions through nitric oxide-cGMP signaling pathway and ion channels.

Formaldehyde (FA) has been linked to the detrimental cardiovascular effects. Here, we explored the effects and mechanisms of FA on rat aortas both in vivo and in vitro. The results presented that FA evidently lowered the blood pressures of rats. The expression levels of BKCa subunits α and ß1 and iNOS of the aortas were up-regulated by FA in vivo. However, FA markedly reduced the levels of Cav1.2 and Cav1.3, which are the subunits of L-Ca2+ channel. Furthermore, the contents of NO, cGMP and iNOS in the aortas were augmented by FA. To further confirm these findings, the mechanisms accredited to these effects were examined in vitro. The data showed that FA contracted the isolated aortic rings at low concentrations (<300 µM), while it relaxed the rings at high concentrations (>500 µM). The FA-induced vasoconstriction at low concentrations was blocked partly by an inhibitor of ACE. The relaxation caused by FA at high concentrations was attenuated by the inhibitors of NO-cGMP pathway, L-Ca2+ channel and BKCa channel, respectively. Similarly, the expression of iNOS was strongly enhanced by FA in vitro. The effects of FA on the aortic rings with endothelium were significantly greater than those on the rings without endothelium. Our results indicate that the vasoconstriction of FA at low concentrations might be partially pertinent to endothelin, and the FA-caused vasorelaxation at high concentrations is possibly associated with the NO-cGMP pathway, L-Ca2+ channel and BKCa channel. This study will improve our understanding of the pathogenic mechanisms for FA-related cardiovascular diseases.

Healable, Transparent, Room-Temperature Electronic Sensors Based on Carbon Nanotube Network-Coated Polyelectrolyte Multilayers.

Transparent and conductive film based electronics have attracted substantial research interest in various wearable and integrated display devices in recent years. The breakdown of transparent electronics prompts the development of transparent electronics integrated with healability. A healable transparent chemical gas sensor device is assembled from layer-by-layer-assembled transparent healable polyelectrolyte multilayer films by developing effective methods to cast transparent carbon nanotube (CNT) networks on healable substrates. The healable CNT network-containing film with transparency and superior network structures on self-healing substrate is obtained by the lateral movement of the underlying self-healing layer to bring the separated areas of the CNT layer back into contact. The as-prepared healable transparent film is assembled into healable transparent chemical gas sensor device for flexible, healable gas sensing at room temperature, due to the 1D confined network structure, relatively high carrier mobility, and large surface-to-volume ratio. The healable transparent chemical gas sensor demonstrates excellent sensing performance, robust healability, reliable flexibility, and good transparency, providing promising opportunities for developing flexible, healable transparent optoelectronic devices with the reduced raw material consumption, decreased maintenance costs, improved lifetime, and robust functional reliability.

Effects of sodium metabisulfite on the expression of BK(Ca), K(ATP), and L-Ca(2+) channels in rat aortas in vivo and in vitro.

Sodium metabisulfite (SMB) is most commonly used as the preservative in many food preparations and drugs. So far, few studies about its negative effects were reported. The purpose of this study was to investigate the effect of SMB on the expression of big-conductance Ca(2+)-activated K(+) (BKCa), ATP-sensitive K(+) (KATP), and L-type calcium (L-Ca(2+)) channels in rat aorta in vivo and in vitro. The results showed that the mRNA and protein levels of the BKCa channel subunits α and ß1 of aorta in rats were increased by SMB in vivo and in vitro. Similarly, the expression of the KATP channel subunits Kir6.1, Kir6.2, and SUR2B were increased by SMB. However, SMB at the highest concentration significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. These results suggest that SMB can activate BKCa and KATP channels by increasing the expression of α, ß1, and Kir6.1, Kir6.2, SUR2B respectively, while also inhibit L-Ca(2+) channels by decreasing the expression of Cav1.2 and Cav1.3 of aorta in rats. The molecular mechanism of SMB-induced vasorelaxant effect might be related to the expression changes of BKCa, KATP, and L-Ca(2+) channels subunits. Further work is needed to determine the relative contribution of each channel in SMB-mediated vasorelaxant effect.

Effects of gaseous sulfur dioxide and its derivatives on the expression of KATP, BKCa and L-Ca(2+) channels in rat aortas in vitro.

Epidemiological investigations have revealed that sulfur dioxide (SO2) exposure is linked to cardiovascular diseases. Our previous study indicated that the vasorelaxant effect of SO2 might be partly related to ATP-sensitive K(+) (KATP), big-conductance Ca(2+)-activated K(+) (BKCa) and L-type calcium (L-Ca(2+)) channels. The present study was designed to further investigate the effects of gaseous SO2 and its derivatives on the gene and protein expression of these channels in the rat aortas in vitro. The results showed that the mRNA and protein levels of the KATP channel subunits Kir6.1, Kir6.2 and SUR2B of the rat aortas in SO2 and its derivatives groups were higher than those in control group. Similarly, the expression of the BKCa channel subunits α and ß1 was increased by SO2 and its derivatives. However, SO2 and its derivatives at 1500µM significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. Histological examination of the rat aorta tissues showed moderate injury of tunica media induced by SO2 and its derivatives at 1500µM. These results suggest that SO2 and its derivatives can activate the KATP and BKCa channels by increasing the expression of Kir6.1, Kir6.2, SUR2B and α, ß1, respectively, while also inhibiting the L-Ca(2+) channels by decreasing the expression of Cav1.2 and Cav1.3 of the rat aortas. The molecular mechanism of the vasorelaxant effect of SO2 and its derivatives might be related to the expression changes of KATP, BKCa and L-Ca(2+) channel subunits, which may play a role in the pathogenesis of SO2-associated cardiovascular diseases.

Hierarchical NiAl layered double hydroxide/multiwalled carbon nanotube/nickel foam electrodes with excellent pseudocapacitive properties.

The performances of pseudocapacitors usually depend heavily on their hierarchical architectures and composition. Herein, we report a three-dimensional hierarchical NiAl layered double hydroxide/multiwalled carbon nanotube/nickel foam (NiAl-LDH/MWCNT/NF) electrode prepared by a facile three-step fabrication method: in situ hydrothermal growth of NiAl-LDH film on a Ni foam, followed by direct chemical vapor deposition growth of dense MWCNTs onto the NiAl-LDH film, and finally the growth of NiAl-LDH onto the surface of the MWCNTs via an in situ hydrothermal process in the presence of surfactant sodium dodecyl sulfate. The MWCNT surface was fully covered by NiAl-LDH hexagonal platelets, and this hierarchical architecture led to a much enhanced capacitance. The NiAl-LDH/MWCNT/NF electrode has an areal loading mass of 5.8 mg of LDH per cm(2) of MWCNT/NF surface. It also possesses exceptional areal capacitance (7.5 F cm(-2)), specific capacitance (1293 F g(-1)), and cycling stability (83% of its initial value was preserved after 1000 charge-discharge cycles). The NiAl-LDH/MWCNT/NF material is thus a highly promising electrode with potential applications in electrochemical energy storage.

A hierarchical Ni-Co-O@Ni-Co-S nanoarray as an advanced oxygen evolution reaction electrode.

Developing an efficient electro-catalyst for water oxidation is essential for improving the performance, which holds the key for a number of energy conversion and storage devices. Here we report an effective method for fabricating a Ni-Co-O@Ni-Co-S hierarchical nanoarray, which showed a significantly improved activity relative to Ni-Co-O nanowire arrays for oxygen evolution reactions. The enhanced performance was attributed to the secondary formed Ni-Co-S nanoplatelets which not only acted as efficient electrocatalysts, but also facilitated the electrolyte penetration and increased the surface area.