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This paper seeks to address the preparation of new compositions of hydrophobicizing liquids as release agent for press moulds in the production of plastic articles of all kinds of polymers.

Mixtures of thermo‐stable polyethers (copolymer of ethylene oxide and propylene oxide) and polyols esters/mixed esters in the presence of phenothiazine as antioxidant were prepared and tested.

All compositions were tested and compared with silicone oil polymethylsiloxane‐100 (PMS‐100). The lubricant was manually applied on a hot surface (160‐190°C) of tray of press mould, without any change in the operating cycle. The finished products were easily removed from press mould, and showed higher durability. The release agent was also checked for production of polyethylene lids by automatic moulding at 170‐200°C, and 17 lids have been obtained on one application. This is quite a good result compared with silicone oil PMS‐100, which produced only four to five lids.

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern spectroscopy techniques.

In order to obtain compositions of optimum properties a lot of mixtures were prepared and tested. Only compositions which showed suitable properties were reported.

This paper provides detailed information on the experimental preparation of 37 compositions for hydrophobicizing mould release agents. Testing of different obtained hydrophobicizing liquids showed positive results, in production of plastic household articles, over silicone oil PMS‐100. The finished products were easily removed from press mould and prepared hydrophobicizing liquids showed higher durability than silicone oil PMS‐100. The obtained compositions are also favored from the point of view of commercial availability and ecology and can be considered as replacements for PMS‐100 release agent.

Artificial intelligence (AI) has started to receive attention in the field of digital entrepreneurship. However, few studies propose AI-based models aimed at assisting entrepreneurs in their day-to-day operations. In addition, extant models from the product design literature, while technically promising, fail to propose methods suitable for opportunity development with high level of uncertainty. This study develops and tests a predictive model that provides entrepreneurs with a digital infrastructure for automated testing. Such an approach aims at harnessing AI-based predictive technologies while keeping the ability to respond to the unexpected.

Based on effectuation theory, this study identifies an AI-based, predictive phase in the “build-measure-learn” loop of Lean startup. The predictive component, based on recommendation algorithm techniques, is integrated into a framework that considers both prediction (causal) and controlled (effectual) logics of action. The performance of the so-called active learning build-measure-predict-learn algorithm is evaluated on a data set collected from a case study.

The results show that the algorithm can predict the desirability level of newly implemented product design decisions (PDDs) in the context of a digital product. The main advantages, in addition to the prediction performance, are the ability to detect cases where predictions are likely to be less precise and an easy-to-assess indicator for product design desirability. The model is found to deal with uncertainty in a threefold way: epistemological expansion through accelerated data gathering, ontological reduction of uncertainty by revealing prior “unknown unknowns” and methodological scaffolding, as the framework accommodates both predictive (causal) and controlled (effectual) practices.

Research about using AI in entrepreneurship is still in a nascent stage. This paper can serve as a starting point for new research on predictive techniques and AI-based infrastructures aiming to support digital entrepreneurs in their day-to-day operations. This work can also encourage theoretical developments, building on effectuation and causation, to better understand Lean startup practices, especially when supported by digital infrastructures accelerating the entrepreneurial process.

Although business incubators are widely used support mechanisms for innovative entrepreneurship, the literature still lacks theoretically based explanations of how the incubation process creates value for stakeholders. This study aims to address this gap by developing a conceptual model, and related research propositions, that explains how the entrepreneurial logic in use by an incubator influences the incubation process (selection criteria and service offering) and performance.

Integrating the effectuation and entrepreneurial opportunities literature, which shares common conceptualizations about how the predictability of the future affects entrepreneurial action, the authors posit two archetypes of entrepreneurial logic that are associated with different incubation processes (causal or effectual) and two archetypes of opportunity attributes (discovery- or creation-based) that affect the incubation process needed to support their development.

Juxtaposing these archetypes, the proposed cross-level conceptual model specifies four levels of fit (ideal, surplus, deficit and mismatch) between the incubation process and the opportunity attributes of individual ventures, which directly influence venture performance (high, moderate and low). In turn, an incubator's performance is largely shaped by the overall performance of ventures in its portfolio.

This paper responds to the call for theory-building that links the antecedents and outcomes of the incubation process across levels of analysis. In addition to developing a conceptual model and research agenda at the intersection of entrepreneurship and business incubation, the proposed model also has implications for incubator directors deciding how to allocate limited resources, and for public/private sector administrators interested in leveraging investment in business incubators.

The purpose of this study is to answer the following questions. What kind of entrepreneurial identities do students have that motivate them to choose either of the entrepreneurship course and university-based incubator? How do students involve in the entrepreneurship ecosystem at university based on their entrepreneurial identity?

For this study, the author began to gather information using previous knowledge and any aspect of a work, namely, from the literature review to represent interpretive syntheses of the meaning-making literature review addressing the research question.

This study suggests what happens to entrepreneur students from academia and the reason that they end up in one of the two aforementioned paradigms. This paper aims to underpin the issue of how various entrepreneurial identities of students cause substantial contributing factors in forming such entrepreneurial activities at university and throughout the entire innovation ecosystem.

Almost all of the content of the entrepreneurship education (EE) courses and incubator training is oriented towards consensual entrepreneurship methods, in accordance with entrepreneurship education. Although the core contents of the EE courses and university-based incubators’ training are the same, the outcomes are quite different.

This study considers the students’ entrepreneurial identities with a focus on their point of view that led them to end up in one of the two common entrepreneurship resources at universities: the EE course and entrepreneurial activities related to university-based incubators.

The term Lean Startup (LS) was coined by Eric Ries, and his 2011 book has popularized the concept with organizations, both startups and established organizations, implementing LS. However the empirical grounding is thin and for a long time this subject has been neglected by academia. The purpose of this paper is to present a systematic literature review (SLR) on LS, while highlighting core knowledge and identify gaps.

A SLR was carried out based on the Preferred Reporting for Systematic Reviews and Meta-Analyses (PRISMA) protocol of Scopus and Web of Science databases. In total, 45 articles published in journals and conferences over 10 years were collected which revealed a number of LS research gaps.

The SLR revealed the tools and methods associated with LS, most cited pros and cons, reasons that cause LS failure, the challenges that companies face in the implementation of LS, and critical success factors (CSFs) that can support these challenges and minimize the reasons for failure.

The findings of the study can be beneficial to practitioners and senior managers in organizations who wish to delve into the journey of LS. The study also discloses challenges and barriers that can hinder the implementation of LS.

Academic publications regarding LS are sparse and this SLR is one of the first SLRs to explore both the critical failure factors (CFFs) and the CSFs based on peer-reviewed journal and conference proceedings.

To prepare semi‐synthetic oils satisfying the classification API SF/CC and SAE 10W30 from mineral base oils derived from high paraffinic petroleum, synthetic alkylbenzenes base oils, and suitable additives.

The mixtures of base mineral oils of deep hydro‐isomerization derived from high‐paraffinic petroleum (viscosity at 100°C is 12.5 cSt) and the mixtures of the synthetic alkyl aromatics oils with the naphthenic components (viscosity at 100°C of 8.0 cSt) were used as base oil. viscosity‐temperature properties, pour points, and flash points were modified by mixing of suitable additives. Octan M‐1, Octan M‐2, Octan M‐3, and Octan M‐4 oils were obtained by application of suitable additives into the prepared base oils B‐C. In order to get the SAE 10W30 requirements the viscous additive was added (0.4‐0.6 mass percent) to prepared base oils. For obtaining the API/SF/CC grade oils, package additive (Hitec 9229) additive was added (4.7 mass percent) to the mixture. The oil (Octan M‐1) was tested in the engine of Mercedes‐Benz model 230 car and positive results over 20,000 km running.

It was observed that, viscosities and pour points change linearly as the mass percent of alkylbenzenes the in the base oil mixture is changed. This realizes the possibility of the creation of semi‐synthetic motor oil of desired properties in the case of lack of other low‐viscosity synthetic component such as poly‐á‐olefins, diester and polyester oil. The obtained oils are useful for service in relatively mild climatic conditions (average temperature of the winter period −15 to −30°C).

The obtained oils cannot fully satisfy the requirements of the engines by pour point and low‐temperature characteristics in the absence of additives.

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

Details practical information on preparation of four semi‐synthetic oils satisfying the classification API SF/CC are reported.

Business accelerators facilitate new venture creation, and most research on the subject focuses on the performance of accelerated ventures. This paper aims to understand what entrepreneurs value in business accelerators and how this differs for women- and men-led ventures. The authors suggest that venture growth stage may play a mediating role in these relationships.

The authors use the resource-based view perspective to develop models of women- and men-led ventures’ valuation for business accelerator services. They also draw upon a database of 2,000 US entrepreneurs.

The authors found that, compared to men, women entrepreneurs place greater value on knowledge transfer benefits (i.e. business skills education) but lower value on networking benefits offered by accelerators. However, there are no significant differences in the valuations for these services between genders for high-growth ventures. Additionally, compared to men, women leading high-growth ventures place greater value on access to potential investors or funders.

This research serves as a practical guide for accelerator administrators and marketers who seek to adjust their business support offerings based on the value placed for the services by different populations of entrepreneurs.

The authors provide a business accelerator user’s perspective and highlight differences in valuation of accelerator services by women- and men-led ventures at different stages of venture growth.

Startups have attracted increased attention over the past years. While entrepreneurs develop startups to capture new business opportunities, also large companies are turning to these fast-growing organizations in efforts to become more agile. However, managing business model innovation and validation is challenging. A number of methodologies, like the Lean Startup (LS), emerged to reduce uncertainties concerning innovation-based projects, and to contribute to business model validation. Despite its popularity, the literature on the LS and its key underpinnings (Agile Methodologies and Customer Development) is sparse, lacking an integrated and structured analysis of their impacts and potentialities. The paper aims to discuss this issue.

The authors conducted a comprehensive systematic literature review on the topic fully analyzing a final set of 71 papers.

There is a turning point in the research stream’s maturity with publications in conferences and major journals, with the predominance of empirical investigations in the European region. Articles on the topic are on the rise in several technology fields. However, the literature on the subject falls short on providing guidance to assist practitioners and scholars on the adoption and investigation of these methodologies.

The paper provides guidance for practice by presenting a staircase roadmap for the LS implementation drawing from the final set of papers reviewed.

The study categorizes the current literature through a concept map, and offers a structured research agenda beyond the categories from the thematic analysis.

The aim of this paper is to focus on the production of mixed‐synthetic diester base oils from the waste of electrochemical production of sebacic acid (mixtures of methyl esters of dicarboxylic acids, HOOC(CH₂)nCOOH, n=4, 6, 8).

The mixtures of methyl esters of dicarboxylic acids ((CH₂)n, n=4, 6, 8) are transesterified by pure alcohols and also different mixtures of aliphatic monohydric alcohols, C6‐C10 of iso‐ and normal structure, in the presence of a new catalyst system (tetra‐n‐butyl orthotitanate, Ti(O‐n‐Bu)₄). The effects of starting materials ratios on the reaction progress and characteristic features of the obtained diester oils have been studied.

The obtained mixed diester oils showed similar thermal properties and low pour point (minimum −70°C), and improved viscosity‐temperature properties compared with commercially available dioctyl sebacate (DOS) and dioctyl adipate (DOA) diester oils.

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The mixtures of methyl esters of dicarboxylic acids obtained from different batches of sebacic acid production have different molar ratios and must be analyzed before use. The process is based on transesterification reactions of methyl esters of mixture of the aliphatic dicarboxylic acids ((CH₂)n, n=4, 6, 8) by mixture of aliphatic alcohols having iso‐ and normal structure in the presence of a new transesterification catalyst (mixture of p‐toluene sulfonic acid and tetra‐n‐butyl orthotitanate). The obtained mixed diester oils showed similar thermal properties, low pour point (minimum −70°C) and improved viscosity‐temperature properties compared with commercially available DOS and DOA diester oils.

The paper illustrates a new process for the production of mixed‐synthetic diester base oils.

This chapter takes an alternative route to inquiry by drawing on intersubjectivity as a way to challenge taken-for-grantedness in entrepreneurship tools. The authors elaborate on how inter-ethnography can be used to discuss various aspects of teaching tools in entrepreneurship education (EE), where the Business Model Canvas (BMC) serves as example. The aim is to initiate a meta-discussion based on education theory on the purposes of tools that risk being taken-for-granted in teaching. The chapter also raises awareness of the difference between the functional and psychological sides of tools, wherein both visuals/graphics and words play a critical role. As a result, a reflective framework is developed as to challenge the existing use and understanding of teaching tools. The framework combines Biesta’s thought on purpose and desirability in education (i.e. qualification, socialisation and subjectification), and the classic relationships in the didactic triangle between the educator, the students and the subject.