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The paper aims to provide an overview of the e‐resources and services in Tsinghua University Library, Beijing, and describe five campus‐wide user surveys. It states how these user surveys play an important role in service quality enhancement.

Following a brief history of Tsinghua University Library, a summary of the collections and services developed in recent years is given. The library has made a great effort to learn about users' needs and to improve service delivery through a series of user surveys. The paper describes these surveys, including the conclusions and the improvement measures adopted.

Feedback gathered from user surveys provides vital information for improving library services. Through these user surveys, the library received a large amount of data to be analysed and a lot of valuable information, it promoted communication with our users, and the librarian's service literacy has also improved.

An overview of user surveys, including methodology, content, organisation, and implementation process, as well as data analysis, might offer reference and practical experience for other university libraries.

User surveys play an important role in the library's service quality enhancement. The paper provides a useful overview and practical experience of the topic.

The purpose of this paper is to examine the great contributions made by the American library expert, Mary Elizabeth Wood, to Chinese library development.

As a pioneer of the modern library movement Mary Elizabeth Wood devoted herself to a Chinese library career. It was structured according to the following theme: setting up the Boone Library and introducing the modern American public library into China; establishing Boone Library School and initiating Chinese library science education; raising money and appealing for China's library development; helping forward the foundation of the Library Association of China; as well as promoting Chinese library intercommunion and cooperation with the West.

With the background of underdeveloped Chinese librarianship, Mary Elizabeth Wood introduced modern American public library spirit into China, opened the gate of Chinese library science, and promoted Chinese library science.

The paper discusses the library history of China and the role of an American librarian in Chinese library history; thus, it should be of wide interest to researchers involved in library history.

Mary Elizabeth Wood devoted herself to a Chinese library career, and promoted Chinese library science greatly, but research on her is limited. This paper considers her contribution to Chinese library science.

Many attempts to justify the business value of increased investments in information technology (IT) have shown mixed results. While findings from earlier studies have been conflicting, recent firm level studies indicate that IT investments have a positive impact on productivity. However, whether IT adds value to organizations is an on going debating issue. Thus, thus it is worth of further investigation.

The paper employs multiple techniques – a regression, regression trees, and regression splines – and integrate the responses provided from each technique.

While IT investments have a positive impact on productivity, the impact is conditional and is not uniform but depends on the amounts invested in other related areas, such as non‐IT labor, non‐IT capital, and/or IT investments.

The IT impact on productivity can be maximized when investments in other related areas are considered together than when they are considered in isolation. Therefore, IT investment decisions should not be made without consideration of the levels of other investments within an organization to avoid any waste in additional investments in IT.

While most previous studies have studied in terms of its existence or non‐existence of the IT impact, we investigate the conditions under which the IT impact would or would not exist. Thus, our study provides with the opportunity for gaining a deeper understanding of the impact of IT investments on productivity.

This study aims to improve detection efficiency of fluorescence biosensor or a graphene field-effect transistor biosensor. Graphene field-effect transistor biosensing and fluorescent biosensing were integrated and combined with magnetic nanoparticles to construct a multi-sensor integrated microfluidic biochip for detecting single-stranded DNA. Multi-sensor integrated biochip demonstrated higher detection reliability for a single target and could simultaneously detect different targets.

In this study, the authors integrated graphene field-effect transistor biosensing and fluorescent biosensing, combined with magnetic nanoparticles, to fabricate a multi-sensor integrated microfluidic biochip for the detection of single-stranded deoxyribonucleic acid (DNA). Graphene films synthesized through chemical vapor deposition were transferred onto a glass substrate featuring two indium tin oxide electrodes, thus establishing conductive channels for the graphene field-effect transistor. Using π-π stacking, 1-pyrenebutanoic acid succinimidyl ester was immobilized onto the graphene film to serve as a medium for anchoring the probe aptamer. The fluorophore-labeled target DNA subsequently underwent hybridization with the probe aptamer, thereby forming a fluorescence detection channel.

This paper presents a novel approach using three channels of light, electricity and magnetism for the detection of single-stranded DNA, accompanied by the design of a microfluidic detection platform integrating biosensor chips. Remarkably, the detection limit achieved is 10 pm, with an impressively low relative standard deviation of 1.007%.

By detecting target DNA, the photo-electro-magnetic multi-sensor graphene field-effect transistor biosensor not only enhances the reliability and efficiency of detection but also exhibits additional advantages such as compact size, affordability, portability and straightforward automation. Real-time display of detection outcomes on the host facilitates a deeper comprehension of biochemical reaction dynamics. Moreover, besides detecting the same target, the sensor can also identify diverse targets, primarily leveraging the penetrative and noninvasive nature of light.

This paper aims to introduce a novel 4D hyperchaotic fractional-order system which can produce one-to-four-wing hyperchaotic attractors. In the study of chaotic systems with variable-wing attractors, although some chaotic systems can generate one-to-four-wing attractors, none of them are hyperchaotic attractors, which is incomplete for the dynamic characteristics of chaotic systems.

A novel 4D fractional-order hyperchaotic system is proposed based on the classical three-dimensional Lü system. The complex and abundant dynamic behaviors of the fractional-order system are analyzed by phase diagrams, bifurcation diagrams and the corresponding Lyapunov exponents. In addition, SE and C₀ algorithms are used to analyze the complexity of the fractional-order system. Then, the influence of order q on the system is also investigated. Finally, the circuit is implemented using physical components.

The most particular interest is that the system can generate one-to-four-wing hyperchaotic attractors with only one parameter variation. Then, the hardware circuit experimental results tally with the numerical simulations, which proves the validity and feasibility of the fractional-order hyperchaotic system. Besides, under different initial conditions, coexisting attractors can be obtained by changing the parameter d or the order q. Then, the complexity analysis of the system shows that the fractional-order chaotic system has higher complexity than the corresponding integer-order chaotic system.

The circuit structure of the fractional-order hyperchaotic system is simple and easy to implement, and one-to-four-wing hyperchaotic attractors can be observed in the circuit. To the best of the knowledge, this unique phenomenon has not been reported in any literature. It is of great reference value to analysis and circuit realization of fractional-order chaotic systems.

The combination of mobile devices and innovative tools offers new possibilities for the development of a community of practice for design makers. Mobile learning has become an essential method that design makers should adopt. The main content of this study is to explore the characteristics of learning behaviors and learning needs of creative design makers' group in forming a community of practice in the era of mobile learning.

This study conducted questionnaire research on the potentially associated or directly associated population of design makers. The process of the study also combined observational and interview studies to compensate for the lack of questionnaire research.

Based on the support of mobile learning technology, design makers share and co-create to achieve individual development and evolution of learning organizations, and produce creative value. Design-maker communities of practice form common communities in the framework of informal organizations to support continuous individual learning. Convergent interests or concerns in making things, real-world contexts based on makerspaces and hands-on practice based on real projects are the basis for forming design-maker communities of practice. A variety of open-source hardware, software and platforms that can support mobile learning are important for the development of design-maker communities of practice. The design-maker community of practice needs group factors, activity development, physical and technical resources, spatial support and institutional norms to enhance learning behaviors and satisfy learning needs.

The discovery and construction of these associated factors can help creative design practitioners form a lasting and virtuous organizational development. This study facilitates the formation of a social network for learning and knowledge sharing among design-maker communities of practice. It enhances the innovation ability and enthusiasm of design makers according to the population characteristics and learning needs of design makers. This study also facilitates the generation of a positive adaptive maker culture and maker spirit within design maker organizations.

The purpose of this paper is to propose a prediction method of gas-liquid two-phase flow patterns and reveal the flow characteristics in the suction chamber of a centrifugal pump.

A transparent model pump was experimentally studied, and the gas-liquid two-phase flow in the pump was numerically simulated based on the Eulerian–Eulerian heterogeneous flow model. The numerical simulation method was verified from three aspects: the flow pattern in the suction chamber, the gas spiral length and the external characteristics of the pump. The two-phase flow in the suction chamber was studied in detail by using the numerical simulation method.

There are up to eight flow patterns in the suction chamber. However, at a certain rotational speed, only six flow patterns are observed at the most. At some rotational speeds, only four flow patterns appear. The gas spiral length has little relationship with the gas flow rate. It decreases with the increase of the liquid flow rate and increases with the increase of the rotational speed. The spiral flow greatly increases the turbulence intensity in the suction chamber.

A method for predicting the flow pattern was proposed. Eight flow patterns in the suction chamber were identified. The mechanism of gas-liquid two-phase flow in the suction chamber was revealed. The research results have reference values for the stable operation of two-phase flow pumps and the optimization of suction chambers.

This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability, which can find application in the printing industry.

To obtain a good dispersion, PLE was used as a dispersant in pigments dispersion. The colloidal and rheological properties of the PLE-based dispersion, such as particle distribution, zeta potentials and apparent viscosity were evaluated.

The particle sizes of the pigment dispersions were within the range of 150 to 200 nm. The measurement of zeta potentials varied between −24 to −32 mV, revealing a strong surface charge interaction between pigments and PLE. Subsequently, its stability to high-speed centrifuge and freeze-thaw treatment was carefully investigated. To demonstrate the coverage of pigment particles by PLE, thermogravimetric analysis was carried out. Moreover, X-ray diffraction was used to disclose the combined impacts of PLE and ultrasonic power on the crystal structures of the pigments. Finally, the coloring performance and leveling properties of pigment dispersions on cotton substrates were evaluated by measuring their K/S values (color strength), rub and color fastness properties, which possessed good results.

The dispersant used is incompatible with strong oxidizing agents and strong bases. More so, modification to improve its dispersion properties can be studied.

The use of PLE as a dispersant could be readily used in pigment dispersion processes and other suitable applications. PLE could also be used as a co-surfactant in synergy with other surfactants or dispersants in the dispersion process.

The use of PLE in pigment dispersion as well as investigating its coloring properties on cotton fabric is novel and can find various applications in the dying, printing and coating industry.

The purpose of this paper is to study the dimensionless characteristics of a molten salt pump and propose an approach to carry out the modeling experiment by using water instead of molten salts.

External characteristics of the pump were estimated by using the steady flow model and compared with the experimental results. By taking water as the working fluid, the pathlines in the volute of the model pump were validated by the results obtained of high-speed photography. According to the derived dimensionless characteristics of the molten salt pump, the modeling experimental schemes were proposed. Adopting the validated numerical simulation model, the performance of the molten salt pump was studied in detail.

The modeling experimental schemes designed according to the dimensionless characteristics are theoretically feasible. However, to carry out the experiment successfully, factors such as rotational speed, geometric size, flow rate and head should be taken into account. The flow in the pumps is similar under the similar operating condition and the external characteristics of the similar pump can be converted to each other. Compared with transporting water, the decline of the head and efficiency is within 5 per cent when the viscosity is lower than 0.01453 Pa · s. The pump is not suitable for running under the critical Reynolds number of 1.0 × 10⁷.

The current work revealed the relationships among the dimensionless performances of a molten salt pump and proposed a critical Reynolds number Re_Qcr for the pump running.

This study aims to explore the infrared imaging effect of fabrics coated with phase change material microcapsules (PCM-MCs), which are prepared by the initiation of ultraviolet (UV) light.

PCM-MCs were prepared by UV polymerization using paraffin (PA) as core material, polymethyl methacrylate as wall material and ferric chloride as photoinitiator. The effects of emulsifier dosage and emulsification temperature on the properties of PA emulsion were investigated. Scanning electron microscopy, particle size analysis, infrared spectroscopy, differential scanning calorimetry and infrared imaging test were used to characterize the properties of microcapsules.

The PCM-MCs with good morphology and particle size were prepared with 25 cm of the distance between light source and the liquid. The average particle size was 1.066 µm and the latent heat of phase transition was 19.96 J/g. After 100 accelerated thermal cycles, the latent heat only decreased by 1.8%. It had good heat storage stability and thermal stability. The fabric coated by the microcapsules exhibited a variable temperature hysteresis effect when placed in the sun, and presented a color close to the infrared images of the human palm under the external environment temperature close to the human body temperature.

The PCM-MCs prepared based on UV light initiation showed good thermal properties and its coated fabrics had an infrared decoy effect below the temperature of the human body.

This study explored the application of microcapsules in textiles.

The microcapsules had a certain application potential in infrared decoy effect.