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Orange dark tea (ODT) is widely produced in China, but the quality of traditional sunlight-dried ODT is not satisfactory, thus limiting its industrial production. This study compared the effects of traditional sunlight drying and current hot air drying on ODT quality. Sensory evaluation showed that hot air-dried orange dark tea (HAD) had better peel-tea integration and higher sensory score. Compared with sunlight-dried ODT (SLD), HAD exhibited higher contents of polyphenols, flavonoids, hesperidin and limonin. Gas chromatography-mass spectrometry (GC–MS) analysis of volatile components in the two ODTs identified a total of 102 aroma components, where 22 differential metabolites and 4 key aroma substances (linalool, limonene, β-myrcene and sabinene) were screened. Bioactivity analysis showed that HAD had better inhibitory effect against α-glucosidase and α-amylase activity, indicating superior overall quality. Further analysis of the effect of drying temperatures on ODTs quality exhibited that low temperature drying at 40 to 50 °C endowed ODT with lower bitterness and astringency, richer polyphenols, flavonoids, hesperidin, and free amino acids, also indicating better comprehensive quality. All the results indicate that hot air drying outperforms sunlight drying in improving ODT quality. This study provides a basis for process optimization of ODT.

Semi-macrosegregation in continuously cast blooms and its associated carbide banding defects in hot-rolled bars were investigated to explore the characteristics, evolution, and control methods in high-carbon chromium bearing steel. It was found that the semi-macrosegregation exists only in the central equiaxed crystal zone of the blooms, and C, Cr solute elements inside show typical spot-like positive segregation. Carbide banding appears as white bright bands along the rolling direction, composed of high number density M3C carbide particles, with a significant effect on the mechanical properties of the rolled products. The hereditary evolution from semi-macrosegregation to carbide banding was established by means of banded segregation. Morphologically, normal semi-macrosegregation and carbide-typed semi-macrosegregation are formed based on whether Cr-rich primary carbides are generated. These two types of semi-macrosegregation evolved into two kinds of carbide banding respectively, that is, dark bands and bright bands defined according to the ability to reflect light under OM. To alleviate the carbide banding defect in rolling products of high-carbon chromium bearing steel, the morphology and area ratio of equiaxed crystals in continuous cast blooms should be modified. It is observed that the equiaxed crystal ratio in the bloom can be decreased from 62.5 % to 28 % by increasing liquid steel superheat and inhibiting superheat dissipation in the mold through casting practices. Additionally, the morphology of equiaxed crystals is related to the as-cast solidification structure, and when the equiaxed crystal ratio is large, the equiaxed crystals turn out to be coarser ones with only cellular primary dendrite; when the columnar crystals are longer, however, the equiaxed crystals appear as a dendrite structure with fine secondary dendrites. As a result, semi-macrosegregation was improved obviously with the fine dendrite structure splitting the local residual liquid phase, leading to the decrease of the maximum width of carbide banding from 268.41 μm to 73.72 μm, and the increase of mechanical properties in the rolled bar of high-carbon chromium bearing steel.

Based on the application of electromagnetism and hydrodynamics in metallurgy, the selection of the number of inductors as well as the direction of inductor current access is investigated for channel-type induction heating (IH) tundish with dual-channel (D-Ch), three-channel (T-Ch) and four-channel (F-Ch) tundish designs. The results show that when a single inductor is used, the Joule heat power (JHP) and electromagnetic force (EMF) are essentially the same within the two channels of the D-Ch tundish, but in the T-Ch tundish and the F-Ch tundish, the JHP and EMF of channel No.1 (Ch1) is much larger than other channels, which is extremely asymmetric. This will further be reflected in the influence on the flow and temperature consistency of the molten steel in the tundish. When a single inductor is used in the T-Ch or F-Ch tundish, the molten steel flow velocity in Ch1 is 4.2 and 7.4 times higher than that in the symmetric channel, respectively, and the temperature difference at the symmetric strand can be as high as 11 K or more. However, the maximum flow velocity of the molten steel in Ch1 and channel No.2 (Ch2) of the D-Ch tundish is 0.21 and 0.19 m⋅s−1, respectively, and the maximum temperature difference at the symmetrical strand is only 2.3 K. For the tundish with double inductors, the influence of the direction of the access current of the inductors should be taken into account. The inductors of a D-Ch tundish can effectively heat the molten steel only by accessing the same direction current. The physical fields in the intermediate and side channels are significantly different when the same or opposite current is accessed to the dual inductors of T-Ch tundish. The temperature rise rate of the molten steel is 36% higher when the dual inductors of the F-Ch tundish are accessed to the opposite current than when they are accessed to the same current. Therefore, a D-Ch design should be used for the channel-type tundish with a single inductor. And for the channel-type tundish with dual inductors, the same direction current should be accessed under the D-Ch design, and the opposite current should be accessed under the F-Ch design.

ABSTRACTType 2 diabetes mellitus (T2DM) is a leading global health concern. The study estimated the lncRNA UCA1 expression in peripheral blood of T2DM patients and its clinical value for diagnosing T2DM and predicting cardiovascular disease (CVD) in T2DM. A total of 80 T2DM patients (37 cases with T2DM complicated with CVD) were selected, with another 70 healthy people as controls. UCA1 expression was measured, and its diagnostic efficacy for T2DM was assessed. Median UCA1 level divided T2DM patients into UCA1 low expression group and UCA1 high expression group, and its correlation with clinical indicators of T2DM patients was analyzed. Relevance between UCA1 and SADN, YKL-40 or CTRP-3 in T2DM complicated with CVD patients, and independent correlation between UCA1 and CVD in T2DM were evaluated. UCA1 was downregulated in T2DM patients, associated with clinical indicators, and assisted the diagnosis of T2DM. UCA1 was positively-correlated with SADN and CTRP-3, and negatively interrelated with YKL-40. UCA1 low expression was independently linked with and predicted an enhanced risk of CVD in T2DM patients. Briefly, UCA1 low expression assists the diagnosis of T2DM and predicts an increased risk of CVD in T2DM patients.

ABSTRACTA three-dimensional magnetic-flow-heat coupling model was established to study the metallurgical behaviour under different flow control devices in the channel-typed induction heating (IH) tundish. As compared to the prototype tundish, the results suggested that the maximum temperature difference between each strand and the tundish dead zone ratio are decreased by 0.75 K and 5.24% while with a kind of double-port channel even without IH. With an additional setup of dam in the IH tundish, the values mentioned above will drop furtherly by 0.52 K and 0.63%, respectively. The inclined wall of the prototype IH-tundish and its single-side installation of the induction coils, however, produce a downward electromagnetic force (EMF) at the channel exit eccentrically, which will make molten steel at the exit of the channel to flow downward and aggravate the short-circuit flow tendency at strand 2 (S2). The eccentric downward EMF at the exit of channel port-1 drives the molten steel to flow downward, but which can be depressed by the newly designed dam. In contrast, the eccentric upward EMF at the exit of channel port-2 drives the molten steel to flow upward. With IH turning on, the double-port channel plus dam device can reduce the dead zone ratio by 5.05% compared to the prototype tundish. Meanwhile, both the maximum temperature difference between each strand and the time exceeding the harmful temperature difference (3 K) can be decreased together accordingly.

A three-dimensional magnetic-flow-heat coupling model was established to study the metallurgical behaviour under different flow control devices in the channel-typed induction heating (IH) tundish. As compared to the prototype tundish, the results suggested that the maximum temperature difference between each strand and the tundish dead zone ratio are decreased by 0.75 K and 5.24% while with a kind of double-port channel even without IH. With an additional setup of dam in the IH tundish, the values mentioned above will drop furtherly by 0.52 K and 0.63%, respectively. The inclined wall of the prototype IH-tundish and its single-side installation of the induction coils, however, produce a downward electromagnetic force (EMF) at the channel exit eccentrically, which will make molten steel at the exit of the channel to flow downward and aggravate the short-circuit flow tendency at strand 2 (S2). The eccentric downward EMF at the exit of channel port-1 drives the molten steel to flow downward, but which can be depressed by the newly designed dam. In contrast, the eccentric upward EMF at the exit of channel port-2 drives the molten steel to flow upward. With IH turning on, the double-port channel plus dam device can reduce the dead zone ratio by 5.05% compared to the prototype tundish. Meanwhile, both the maximum temperature difference between each strand and the time exceeding the harmful temperature difference (3 K) can be decreased together accordingly.

ABSTRACTAs-cast inherited defects are usually observed especially in quenched and tempered (QT) steels, such as 42CrMo due to macro-segregation. A three-dimensional numerical model has been presented to reveal the heat mass transportation and solidification behaviour of the molten steel in a 250 mm × 280 mm continuously cast bloom with and without M-EMS application. The reliability of the coupled model was proved by comparing the measured data of magnetic flux density with the calculated one along the centreline. The research indicates that the phenomena of a decrease in the solidification rate and an increase in molten steel washing velocity are observed as the current intensity increases from 0 to 450 A, which leads to a decrease of the minimum segregation degree by 0.039 and an increase of the width of the harmful negative segregation band by 3.6 mm. The washing effect that increases with the current intensity can reinforce the heat transfer between molten steel and solidification front and stimulate the formation of the equiaxed crystal. Accordingly, the average, local temperature gradient, and the superheat degree at the centre of mould exit decrease by 0.12, 2.62 K·mm−1, and 2.9 K, respectively, together with an increase of the equiaxed crystal ratio by about 9.44%. It suggests that the M-EMS may lead to the more serious subsurface negative segregation but can improve the equiaxed crystal ratio of bloom castings, which influences the heat treatment performance and flaw detection pass rate of subsequent rolled products.

As-cast inherited defects are usually observed especially in quenched and tempered (QT) steels, such as 42CrMo due to macro-segregation. A three-dimensional numerical model has been presented to reveal the heat mass transportation and solidification behaviour of the molten steel in a 250 mm?×?280 mm continuously cast bloom with and without M-EMS application. The reliability of the coupled model was proved by comparing the measured data of magnetic flux density with the calculated one along the centreline. The research indicates that the phenomena of a decrease in the solidification rate and an increase in molten steel washing velocity are observed as the current intensity increases from 0 to 450 A, which leads to a decrease of the minimum segregation degree by 0.039 and an increase of the width of the harmful negative segregation band by 3.6 mm. The washing effect that increases with the current intensity can reinforce the heat transfer between molten steel and solidification front and stimulate the formation of the equiaxed crystal. Accordingly, the average, local temperature gradient, and the superheat degree at the centre of mould exit decrease by 0.12, 2.62 K·mm-1, and 2.9 K, respectively, together with an increase of the equiaxed crystal ratio by about 9.44%. It suggests that the M-EMS may lead to the more serious subsurface negative segregation but can improve the equiaxed crystal ratio of bloom castings, which influences the heat treatment performance and flaw detection pass rate of subsequent rolled products.

Oxygen vacancy plays an important role in catalytic oxidation of formaldehyde (HCHO), but the inherent drawback of its thermodynamic instability causes the deactivation of catalysts. Hence, improving the thermodynamic stability of oxygen vacancy is a crux during HCHO oxidation. Here, a novel and simple nitrogen doping of MnO2/C catalyst is designed for HCHO oxidation at room temperature. The surface lattice oxygen of MnO2will be activated by nitrogen-doping, which acts as active sites for HCHO oxidation and solves the thermodynamic instability issue of oxygen vacancy. Furthermore, carbon is doped with nitrogen to promote electron transfer and accelerate the HCHO oxidation process. Therefore, the catalytic activity and stability of the catalyst can be significantly promoted, which can completely remove ∼1 ppm HCHO in the tank within 3 h, and remains highly active after 5 cycles at room temperature (RH = 55%). In addition, the excellent removal performance over the prepared catalyst is also attributed to abundant surface oxygen species, amorphous crystallinity, and low reduction temperature. In situ diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) and density functional theory (DFT) calculations reveal the reaction mechanism of HCHO. This strategy provides crucial enlightenment for designing novel Mn-based catalysts for application in the HCHO oxidation field.

The inherent low activity at room temperature has greatly limited the utilization of Co3O4in indoor air purification. In this work, an extremely facile and mild method utilizing the strong oxidation of H2O2was designed to prepare a novel Co3O4-HP catalyst. The Co3O4-HP catalyst exhibits excellent removal activity for low-level concentration (∼1 ppm) of formaldehyde (HCHO) at room temperature. Under the static test mode, it shows 90.62% HCHO removal efficiency in 180 min at an RH of ∼55%. Under the dynamic test mode, it maintains the performance to remove approximately 97.26% of HCHO within 180 min under a GHSV of ∼90,000 mL·h–1·g–1. Additionally, the HCHO removal efficiency of Co3O4-HP is also maintained at around 94.76% under a higher GHSV of ∼150,000 mL·h–1·g–1. Such a satisfying activity is due to abundant oxygen vacancy defects bringing about a large number of surface reactive oxygen species and high redox capacity and oxygen migration capacity. It is also because of the synergistic effect of surface OH groups. This strategy will open an exciting avenue to design outstanding catalysts for HCHO removal by defect engineering and the synergistic effect.

It is reported that Imperata cylindrica, a successful invasive plant in North America, has covered many parts of the United States, especially the southeastern region which is the main rice growing region. The invasion of I. cylindricacould threaten rice production. In this study, we hypothesize that biochar nanoparticles (nano-BC) can reduce the stress from the root exudates of I. cylindrica. Ferulic acid (FA) is a major chemical of I. cylindricaroot exudates, and we selected its analog, salicylic acid, as an experimental control. We found that nano-BC has detoxification effects for rice seedlings under FA treatments. Rice seedlings grow better and the phenotype of rice seedlings recovers after nano-BC application under FA treatments. In comparison to the seedlings treated with FA, the biomass of the seedlings increases 344% and 435% after adding 200 mg kg−1and 400 mg kg−1of nano-BC to the FA treatment in the pot experiment, respectively. Superoxide dismutase activities (antioxidant system index) and malondialdehyde concentration (lipid peroxidation marker) decline after the addition of nano-BC. Additionally, the rice growth is better after the addition of nano-BC in the FA treatment. The total chlorophyll concentration displays a recovery trend, and the recovery rates are 55% and 96% after 400 mg L−1and 400 mg kg−1of nano-BC are added to the FA treatments in the hydroponic and pot experiments, respectively. The expression of three salicylic acid-related genes also demonstrates recovery in the treatment with nano-BC and FA. Therefore, nano-BC is a potential material that can be used to protect rice production from the stress of I. cylindricainvasion.

In recent years, there has been significant development in the large-scale utilisation of round bloom continuous casting, which has led to an increase in the strand spacing of the tundish. However, this increase often accompanies issues such as poor consistency among each strand. This study focuses on the three-strand asymmetric tundish used in super-large round bloom continuous casting and uses a combination of numerical simulation and physical experiment to investigate the impact of different dam and retaining wall structures on the flow, temperature and removal of inclusions in the super-large round bloom tundish. The reliability of the model is verified through isothermal Water model experiments. The results indicate that by employing an optimised flow control structure with a U-shaped retaining wall featuring small diversion holes and a dam near each of strands No.1 and No.3, several improvements are achieved compared to the prototype tundish. The dead zone ratio of the tundish is reduced by 16.33%, the standard deviation of average residence time decreases by 167.07 s, the volume of the tundish's low temperature zone decreases by 7.79% and the total inclusion removal ratio increases by 14.44%. By appropriately incorporating dams, reducing the area of diversion holes and modifying the retaining wall structure in the tundish, the flow, temperature and inclusion removal consistency of each strand can be effectively improved. This enhances the overall metallurgical efficiency of the tundish. Even when encountering strand blocking operation, the dead zone ratio can be further reduced to 22.44% using the optimised structure proposed in this study. This demonstrates that the optimised structure not only improves the steady-state metallurgical behaviour of the asymmetric three-strand tundish with large strand spacing for super-large round bloom but is also suitable for addressing unsteady-state metallurgical behaviour caused by on-site working conditions, such as production scheduling or high casting speed. By implementing the findings of this study, it is expected that the efficiency and effectiveness of the super-large round bloom continuous casting process will be significantly enhanced.

ABSTRACTA novel gas blowing mode with different flowrates for two plugs of metallurgical ladle is explored and studied through a sophisticated water model. The results show that this mode can efficiently decrease the mixing time and the total area of the slag eye for most cases, as compared with the conventional mode with same flowrates for two plugs. Generally, a relatively close angle between the porous plugs and a small radial position are beneficial to a decrease in the mixing time of bath, while a relatively far plug radial position leads to a smaller slag eye. In addition, tracers fed from the middle of the dual plugs are proven to be very beneficial to the mixing of the ladle. The slag layer will prolong the mixing time due to its consumption on the stirring energy compared with the situation without slag.

A novel gas blowing mode with different flowrates for two plugs of metallurgical ladle is explored and studied through a sophisticated water model. The results show that this mode can efficiently decrease the mixing time and the total area of the slag eye for most cases, as compared with the conventional mode with same flowrates for two plugs. Generally, a relatively close angle between the porous plugs and a small radial position are beneficial to a decrease in the mixing time of bath, while a relatively far plug radial position leads to a smaller slag eye. In addition, tracers fed from the middle of the dual plugs are proven to be very beneficial to the mixing of the ladle. The slag layer will prolong the mixing time due to its consumption on the stirring energy compared with the situation without slag.

High strain isothermal compression tests at temperatures of 700–1200°C and strain rates of 0.1–50?s-1were performed in a Gleeble-3800 thermal simulator to investigate the hot deformation behaviour of a high-alloy Cr–Co–Mo–Ni gear steel, and the constitution equation and hot processing map were established based on these experiments. The results show that the flow stress can be described by the constitutive equation in hyperbolic sine function, and the optimum hot working regions are at the temperature of 1000–1100°C and strain rate of 0.3–1.0?s-1. Optical microscopy observations of austenite grains indicate that dynamic recrystallisation occurs when the deformation temperature is over 900°C. The forging was successfully produced on the basis of the above-described researches.

ABSTRACTHigh strain isothermal compression tests at temperatures of 700–1200°C and strain rates of 0.1–50 s−1were performed in a Gleeble-3800 thermal simulator to investigate the hot deformation behaviour of a high-alloy Cr–Co–Mo–Ni gear steel, and the constitution equation and hot processing map were established based on these experiments. The results show that the flow stress can be described by the constitutive equation in hyperbolic sine function, and the optimum hot working regions are at the temperature of 1000–1100°C and strain rate of 0.3–1.0 s−1. Optical microscopy observations of austenite grains indicate that dynamic recrystallisation occurs when the deformation temperature is over 900°C. The forging was successfully produced on the basis of the above-described researches.

The effect of a dissipative ladle shroud (DLS) on mixing in tundish was investigated, compared with that of a conventional ladle shroud (CLS) using mathematical and physical modelling. The tracer profiles of mathematical results, achieved using large eddy simulation, were validated by physical observations employing high-speed cinephotography. The design of a DLS dramatically changed the flow patterns and contributed the intermixing of fluid elements inside the ladle shroud. The vortex flow encouraged the turbulent mixing and was verified by tracking of physical tracer dispersion inside the DLS. Residence Time Distribution (RTD) curves were obtained in two different sized tundishes to examine the mixing behaviours. The findings indicated that the DLS benefited the tundish mixing in terms of increasing active volume. The effect seemed to be more remarkable in the smaller tundish. The DLS gave rise to a more plug-like flow pattern inside the tundish, showing potential to shorten the transition length during grade change.

Wind power in China has experienced fast development in recent years. However, areas rich in wind power resources are often far away from loads centers, which leads to weak connection between wind turbines and power grid. When a grid fault occurs, new transient characteristics in weak grid integrated with doubly-fed induction generators (DFIGs) may present, such as voltage phase angle jump. Current control strategies for wind turbine with strong grid connection are hard to be adapted under weak gird connection. This paper explores the transient characteristics of DFIGs under voltage phase angle jump through analyzing the operation and control characteristics of DFIGs connected into weak grid when the voltage phase angle jumps. Fault ride through (FRT) control strategy of DFIGs based on adaptive phase-locked loop is proposed to adapt weak grid condition. The reference frame of the proposed strategy will be changed in real-time to track the operation condition of DFIGs according to the terminal voltage, and different phase tracking method is adopted during the grid fault. Field data analysis and time domain simulation are carried out. The results show that voltage phase angle jumps when a grid fault occurs, which weakens the FRT capability of DFIGs, and the proposed FRT control strategy can optimize transient characteristics of DFIGs, and improve the FRT capability of DFIGs.

Background and Purpose:We sought to investigate the clinical characteristics and echocardiographic changes of cryptogenic perforator infarction (PI) patient with patent foramen ovale (PFO).Methods:From Jan 2015 to Sep 2018, patients diagnosed with cryptogenic stroke were retrospectively included in our study. All patients received transthoracic echocardiography (TTE) and transcranial Doppler (TCD). PFO was diagnosed by the bubble test of TCD. Comparisons of clinical features and TTE findings were performed firstly in PI patients, between PFO and non-PFO, and then in patients with PFO, between PI and cortical infarction (CI).Results:A total of 228 patients were retrospectively analyzed. PFO was detected in 80 of the patients, of those, 23.7% (19/80) had pure PI (PFO-PI) and 76.3% (61/80) had CI (PFO-CI). In patients without PFO, 30.4% (40/148) had pure PI (non-PFO-PI). Compared with non-PFO-PI, PFO-PI associated with a higher proportion of vertebrobasilar circulation infarctions (VCI) (47.5% vs. 17.9%, p= 0.014), lower median left ventricle end-diastolic diameters (LVEDd) (46mm vs. 50mm, p= 0.016) and lower peak E-wave velocity (57cm/s vs. 72cm/s, p= 0.022). In PFO patients, PFO-PI was detected with a lower median aorta root diameters (32mm, p=0.004) and lower median LVEDd (46mm, p=0.024) than PFO-CI (34mm and 48mm, respectively).Conclusions:Higher proportion of VCI was found in PFO-PI. Lower LVEDd, lower Em and without aortic root dilatation were three echocardiographic features associated with PFO-PI in cryogenic PI patients.

In the condition of connecting large scale doubly-fed induction generators (DFIGs) into weak grid, the closely coupled interactions between wind generators and power grid becomes more severe. Some new fault characteristics including voltage phase angle jump will emerge, which will influence the power quality of power system. However, there are very few studies focusing on the mechanism of voltage phase angle jump under grid fault in a weak grid with wind turbine integration. This paper focuses on the scientific issues and carries out mechanism studies from different aspects, including mathematical deduction, field data analysis and time domain simulation. Based on the analysis of transient characteristics of DFIGs during the grid fault, this paper points out that the change of terminal voltage phase angle in DFIGs is an electromagnetism transition process, which is different from conventional synchronous generator. Moreover, the impact on transient characteristics of voltage phase angle are revealed in terms of fault ride through (FRT) control strategies, control parameters of current inner-loop of rotor-side converter and grid strength.

Mg ion-exchanged samples were prepared with acid-washed Shengli lignite. The chemical composition of the ash of the raw sample was determined by X-ray fluorescence. The equilibrium adsorption water contents of samples were determined in a range of relative humidity. The ion-exchange process was characterized by FT-IR, ash content, and pH value. A possible mechanism is proposed for equilibrium adsorption water of ion-exchanged samples at different humidities. The extent of ion-exchange reaction between Mg2+and lignite is controlled by the concentration of Mg2+in MgSO4solution. The effect of Mg2+on equilibrium adsorption water content varies with relative humidity and content of Mg2+. The factor that controls equilibrium adsorption water content at low relative humidity is water interactions with sorption sites, which are Mg2+–carboxyl group complex. At middle relative humidity capillary force between Mg2+–water clusters Mg+(H2O)nand capillary is more important. At high relative humidity, free water–free water interactions are more significant.

To investigate the effects of multiple weak interactions on the binding of phenolic compounds by polymeric adsorbents, macroporous polystyrene (PS) resin and PS‐based adsorbents with different hydrogen‐bond acceptor atoms (PS&bond;CH2(&bond;OCH2CH2)n&bond;OCH3, n = 0, 1, 2, and 3, denoted as PS‐EG0, PS‐EG1, PS‐EG2, and PS‐EG3) were prepared. The phenol adsorption strength order on these adsorbents was PS/PS‐EG0 < PS‐EG1 < PS‐EG2 < PS‐EG3, indicating that the adsorption on PS and PS‐EG0 was driven by hydrophobic and π–π interactions, and the adsorption on PS‐EG1, PS‐EG2, and PS‐EG3 was driven by a hydrogen bond in addition to hydrophobic and π–π interactions. PS‐EG2 may adsorb a second phenol molecule on each binding site and PS‐EG3 may adsorb second and third ones. The adsorption strength of resorcinol increased in the order of PS, PS‐EG1, and PS‐EG2, indicating that the adsorption was driven by 0, 1, and 2 hydrogen bonds in addition to hydrophobic and π–π interactions. Similarly, the adsorption of phloroglucinol on PS, PS‐EG1, PS‐EG2, and PS‐EG3 was driven by 0, 1, 2, and 3 hydrogen bonds in addition to hydrophobic and π–π interactions because the adsorption strength increased in this order. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4652–4658, 2006